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transmitted to the next generation, and, if the hands. He grasps what he brings to his mouth pillars very much of the same colour—perhaps of unfavourable conditions continue, is aggravated with an apish hold. His thumbs are but additional a uniform green or brown. Instead of this, we in it; and thus a morbid variety of the human fingers. He has a leaping walk. He has heavy have sometimes displayed as much beauty as in kind, which is incapable of being a link in the line eyebrows, and short hair on his cheek or face. of progress of humanity. Nature puts it under He is muscular, active, and not dwarfish. He sits the perfect insect-in some cases more-while the ban of sterility, and thus prevents the perma- on the floor in ape fashion, with his genitals al- there are very few caterpillars indeed that are of ent degradation of the race. Morel has traced, ways exposed. He has filthy habits of all kinds. a uniform colour. It is singular, though, that in through four generations, the family history of a He may be called an idiot of the lowest order; very few cases is there any resemblance between youth who was admitted into the asylum at Rouen yet there is a mischievous, brute-like intelligence the markings exhibited by the caterpillar and in a state of stupidity and semi-idiocy; the sum-in his eye. His head is not very small, its greatest those which adorn the wings of the imago promary of which may fitly illustrate the natural circumference being twenty inches and a half, but duced therefrom. Discernment is sadly at fault course of degeneracy when it goes on through in shape it strongly exhibits the ape-form of here amongst those non-entomologists who, from generations, abnormality." the circumstance that they work in gardens or fields, come into contact with many different kinds of caterpillars. As a rule, they notice no differences amongst them, but class them all together as " green varmint" or "blight," and regard them as things to be squashed out of existtence as speedily as possible. So that of many a gardener we might say, parodying the poet's lines, that all he notices is

First generation :-Immorality, depravity, alcoholic excess, and moral degradation, in the great-grandfather, who was killed in a tavern

brawl.

Second generation :-Hereditary drunkenness, maniacal attacks, ending in general paralysis, in the grandfather.

Third generation :-Sobriety, but hypochondriacal tendencies, delusions of persecutions, and homicidal tendencies, in the father.

Fourth generation:-Defective intelligence. First attack of mania at sixteen; stupidity, and transition to complete idiocy. Furthermore, probable extinction of the family; for the generative functions were as little developed as those of a child of twelve years of age. He had two sisters who were both defective physically and morally, and were classed as imbeciles. To complete the proof of heredity in this case, Morel adds that the mother had a child while the father was confined in the asylum, and that this adulterous child showed no signs of degeneracy.

When epilepsy in young children leads to idiocy, as it often does, we must generally look for the deep root of mischief in the family neurosis.

Pinel has recorded the case of an idiot who was something like a sheep, both in respect of her tastes, her mode of life, and the form of her head. She had an aversion to meat, and ate fruit and vegetables greedily, and drank nothing but water. Her demonstrations of sensibility, joy, or trouble, were confined to the repetition of the ill-articulated words bé, ma, bah. She alternately bent and raised her head, and rubbed herself against the belly of the girl who attended her. If she wanted to resist or express her discontent, she tried to butt with the crown of her head; she was very passionate. Her back, her loins, and shoulders were covered with flexible and blackish hairs, one or two inches long. She never could be made to sit on a chair or bench, even when at meals; as soon as she was placed in a sitting posture, she glided on the floor. She slept on the floor in the posture of animals.

Dr. Crichton Browne has now under care in the West Riding Asylum, a deformed idiotic girl, who in general appearance and habits has points of resemblance to a goose; so much so, that the nurses who received her describes her as just like "a plucked goose." Her father died in the asylum, No one can well dispute that in the case of such and her mother's sister was also a patient in it at an extreme morbid variety as a congenital idiot one time. She is 4ft. 2in. in height, has a small is, we have to do with a defective nervous organi-head, and thin and scanty hair, so that the crown sation. We are still, however, without more than of the head is partially bald. The eyes are large, a very few exact descriptions of the brains of round, prominent, and restless, and are frequently idiots. Mr. Marshall has recently examined and covered by the eyelids, as if by a slow forcible effort described the brains of two idiots of European at winking. The lower jaw is large, projecting descent. He found the convolutions to be fewer more than one inch beyond the contracted upper in number, individually less complex, broader, jaw, and possesses an extraordinary range of anteroand smoother than in the apes; " in this respect," posterior, as well as lateral, movement; the whole he says, "the idiots' brains are even more simple configuration of the lower part of the face having than that of the gibbon, and approach that of a somewhat bill-like appearance. The neck is the baboon." The condition was the result neither unusually long and flexible, and is capable of of atropy nor of mere arrest of growth, but consisted being bent backwards so as actually to touch the essentially in an imperfect evolution of the cere- back between the scapula. The cutis anserina is bral hemispheres or their parts, dependent on an generally over the body, but is most marked on arrest of development. The proportion of the the back and dorsal aspects of the limbs, where it weight of brain to that of body was extraordinarily looks exactly as if it had been just deprived of diminished. We learn, then, that when nan is feathers. The inferior angles of the scapulæ stands born with a brain no higher-indeed lower-than prominently ont, and, moving freely with the of an ape, he may have the convolutions fewer in movements of the arms, have precisely the appearnumber, and individually less complex, than theyance of rudimentary wings. The girl utters no are in the brain of chimpanzee and an orang; the human brain may revert to, or fall below, that type of development from which, if the theory of Darwin be true, it has gradually ascended by evolution through the ages.

With the defect of organ there is a corresponding defect of function. But there is sometimes more than a simple defect. A curious and interesting fact, which has by no means yet received the consideration which it deserves, is that, with the appearance of this animal type of brain in idiocy, there do sometimes appear or reappear remarkable animal traits and instincts. There is a class of idiots which may justly be designated theroid, so like brutes are the members of it. The stories of so-called wild men, such as Peter the wild boy, and the young savage of Aveyron, who ran wild in the woods, and lived on acorns, and whatever else they could pick up there, were certainly exaggerated at the time. These degraded beings were evidently idiots, who exhibited a somewhat striking aptitude and capacity for a wild animal life. Dr. Carpenter, however, quotes the case of an idiot girl, who was seduced by some miscreant, and who, when she was delivered,

gnawed through the umbilical cord as some of the

lower animals do.

the ape.

articulate sounds, but expresses pleasure by cackling like a goose, and displeasure by hissing or screeching like a goose, or perhaps like a macaw. When angry, she flaps her arms against her sides, and beats her feet upon the floor. She knows her own name, and understands one or two short sentences, such as "Come here," and "Put out your hand." She recognises the persons who attend upon her and feed her, and is much agitated if touched by a stranger. She cannot feed herself, but swallows voraciously all that is put into her mouth, showing no preference for one article of diet over another. She is dirty in her habits, and no amount of attention has improved her in this respect. She is very fond of her bath, cackling when she is put in, and screeching when she is taken out of it.

(To be continued.)

CHAPTERS ON CURIOUS CATERPILLARS.-JUNE.

THE

BY J. R. S. CLIFFORD. HE thoughtful observer of Caterpillar life can hardly fail to be impressed with the In the conformation and habits of other idiots, endless varieties of shading and colouring, and the most careless observer could not help seeing the numerous variations in form, which occur A striking instance of this kind is described by Dr. Mitchell, Deputy Commissioner amongst these creatures, even if we confiue our in Lunacy for Scotland. "I have never," he attention to our native land. Looking upon the says, seen a better illustration of the ape-faced imago, the butterfly or moth, as the true embodiidiot than in this case. It is not, however, the face alone that is ape-like. He grins, chatters, and screams like a monkey, never attempting a sound in any way resembling a word. He puts himself in the most ape-like attitude in his hunts after lice, and often brings his mouth to help his

ment of the form of each species, we might have said that it would have mattered very little what appearance it had in this or any preparatory stage; and had we no knowledge to the contrary, we might have expected to find all cater

A blight upon the shrubs or trees, Some common blight, 'tis all he seesTo him 'tis nothing more. Well, in these times, the schoolmaster is abroad and we will hope that such being the case he will look a little beyond his books, and getting a good insight into Nature and its operations himself, he will be the better fitted to make "the rising generation," the "coming men," rather wiser in these matters than we can expect to find those who are now too old to be apt pupils of natural history lore.

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A host of caterpillars is feeding in June, especially in the early part of the month; towards the close, however, a good part will have become pupa, and await the change to the imago, or perfect state. There is some difference in each year, according to the weather and the state of the vegetation; this present year (1870) has as yet retarded insect life, and many species are a fortnight or three weeks behindhand. In some of our woods, more particularly in the south of England, the caterpillar of that handsome and remarkably agile butterfly known as the Silverwashed Fritil lary, may be detected by a very careful search in its food plant, the violet. This caterpillar, besides feeding on the species of violet, is also said sometimes to be found on the wild raspberry, but this is extremely doubtful. As such lowgrowing plants cannot be "beaten," the best plan is to crouch down and turn over the leaves, disregarding the stiffness in the back thereby produced, and keeping in view the fact that the caterpillar has the trick of falling off the plant at a very slight touch, doubling itself up partly. The parent butterflies deposit their eggs in July or August, and as these hatch shortly after, and the caterpillars are not adult until the beginning of June, they thus pass about nine months in this state. The ground colour is black; down the back are two yellowish stripes, with a black stripe between them; along the sides in a triple series are delicate lines of a rust colour. On each segment are six spires, which give off fine bristles; on the second segment there are two out of the six, which project over the head of the caterpillar, and have black tips. (See Fig. 1.) Suspending itself against some twig or stem, when it has ceased to eat, the caterpillar's skin is cast off and the chrysalis state assumed, and in this case the name is really correct, for the shell of the chrysalis is decorated with spots and dashes of gold.

singularly-formed Comma Butterfly (Vanessa C. In the early part of the present century, the Album) was taken pretty freely near the metropolis; it has now disappeared, nor does it apparently occur in the southern and eastern counties of England. In Herefordshire, Mr. Newman reports it as still occurring, and in the Lake District, and a few other localities, individuals are seen on the wing most seasons. During 1864, an entomologist obtained the caterpillar of this species, and it is one of some singularity, feeding, as far as observed, only upon the hop-vine. As it is sluggish in its movements, and a day-feeder, it might probably be obtained by beating this climber. It is also supposed to feed on the currant and on nettles. Like the preceding, it has two the caterpillar of the Comma they actually spring processes projecting in front of the head, but in from the head, and are of a horny nature; these are black, as is the head and the next segment of the body, though the general colour of the remainder is grey, chequered with fulvous; from the seventh to the twelfth segment there is a white stripe down the back; on the sides and back are seven rows of branched spines; the eyes, as may be observed by a magnifier, are crowded to

FIG. 1.

gether. The chrysalis is suspended, head downwards, from some leaf-stalk, and has a few silver blotches, on an umber ground; it is also marked with fine black lines. The butterfly emerges in August and September; it is also found in the spring of the year, and individuals then on the wing have possibly lived through the winter.

Common in most parts of Britain, and occuring also in Ireland, is the moth known as the Beaded Chestnut. (Anchocelis Pistacina.) The caterpillars emerge in the spring from eggs laid the previous autumn, and as they feed on the buttercup and other meadow plants growing amongst the grass; they may be conveniently taken by sweeping the grass which is growing for the hay crop, but not during the middle of the day. They fall into the net rolled up closely, but soon relax and march off briskly, and present, as they move, an odd appearance, for, at the interstice of each segment is a fold of skin of a yellow colour, and these folds appear and disappear, looking like yellow rings. The body is velvety and cylindrical, apple-green in tint, with an extremely slender white stripe down the back, and

EGGER CATERPILLAR.- Described in No. 266.

The caterpillar of the Small The Author stated that when, in 1828, the Chocolate Tip (Clostera Reclusa), late Mr. J. B. Neilson (M. Inst. C.E.) intromay be beaten off dwarf sallows duced the plan of heating the air employed as in many places throughout England blast, by means of iron placed in or near a fire, in this mouth. It is slightly hairy, the increase of temperature was at first only marked with grey and yellow, the from 60 deg. to 100 deg. Fahr. Subsequently, under surface, legs, and claspers Mr. Neilson obtained a temperature of 600 deg. being smoke-coloured, and the head or 650 deg., and the pipe stoves had since been black. The cocoon is spun amongst urged up to 900 deg., and in a few cases to the leaves, and the moth flies forth 1000 deg. The wear and tear, however, with in August, giving birth to another such temperatures of blast were considerable. brood of caterpillars in September. there was great loss of heat by conduction, and A much handsomer caterpillar than the pipe stoves were, as a rule, worked in a leaky that of Reclusa is its congener, the condition, necessitating the expenditure of engine Scarce Chocolate Tip. (C. ana- power for blowing air uselessly. choreta), which, however, no entomologist is very likely to find at large, as it is of exceeding scarcity. Nevertheless, specimens of the moth are common enough in collections, nearly all of which are the descendants of some caterpillars found at Folkestone, a few years since. It is a species which will breed in confinement, and by this means an abundance of the caterpillars have been got year after year. The general hue of the body is velvety black, mottled with smoky-grey; a stripe of dingy white runs down the back, and when the caterpillar is crawling, we can perceive that this apparent stripe is composed of square markings, which are connected by lines running between the segments; a double series of similar markings runs along the sides, one row above the spiracles, the other below them; there is a hump of chestnut-brown on the fifth and twelfth seg ments; that on the fifth is surrounded by a white patch; in addition there are smaller prominences on three other segments; the head is black, and also the legs; the claspers of a smoky hue. Towards the end of June, or early in July, this caterpillar (at least, when in captivity) has reached its full size; and spins itself a cocoon between the leaves of the food-plant; it apparently thrives best on sallow or poplar.

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A truly ferocious caterpillar is that from which the rather elegant moth, the Dun Bar (Cosmia Trapezina), is developed. So eager for prey is he that, when he is beaten into the net or umbrella, ere he has hardly recovered from the shock, he begins to crawl with rapidity after some unfortunate smaller caterpillar that may be at hand, especially preferring that of the Common Winter Moth; and Mr. Newman points out the curious fact, that the caterpillar of the Dun Bar does not seize its prey by the extremity, should that be nearest, but advances until he can grasp the neck of the victim. He rarely devours the body entirely, though his appetite is considerable, preferring, after awhile, to look after a fresh victim. This caterpillar is found on oak and hornbean, the leaves of which it probably eats occasionally, though most partial to animal food. In appearance it is of a dull green colour, the body plump, and the head rather narrower, and shining; there are five pale stripes running from head to tail, and it is also freckled over with numerous small warts, which are black, surrounded by a white ring. The under side, legs, and claspers are of a delicate green. It is adult about the middle of June, and changes to a chrysalis on the surface of the ground; the moth appearing a few weeks after.

A not very common moth is known as the broader one along the sides; there are also a Lilac Beauty (Pericallia Syringaria), and it few dots sprinkled along the back. Early in June, deserves the name it bears, for the wings, which these caterpillars enter the earth, and beneath it are of a lustrous grey, are tinged with red and form compact cocoons of grains intermingled yellow, mingled with white and brownish markwith silk. It has been noticed by Mr. Newman ings. The caterpillar feeds on lilac and other that they remain some weeks unchanged, but ulti- shrubs in this month; when of full size, it is mately become chrysalides, which produce moths rather of a rose-coloured hue generally, though in September and October. An instance how sometimes grey, along the back is a pale line, and certain species simulate the appearance of the there are two singular processes, like hooks, on plants on which they feed is furnished by the the ninth segment, and four rather conspicuous caterpillar of the Mallow Moth. (Eubolia Cerrina- warts on the sixth and seventh segments. The ria.) When the Common Mallow is shaken, and chrysalis is enclosed in a silken cocoon of slight there are any of these caterpillars feeding upon it, texture, and it displays numerous brown stripes they roll themselves into rings, the legs, head, and spots. I believe this species is partial to and claspers being hidden, and resemble the seed woodlands-at least, this appears to be the case in of the plant, well-known to all country children the south of England. as "cheeses;" also when not disturbed they extend themselves along the stalks, to which they assimilate in colour, and thus again escape notice. The whole body is covered with minute warts, REGENERATIVE HOT BLAST FURNACES. each tipped with a tiny bristle; these are white, while the general colour is dull green; down the back is a darker line, showing the course of the alimentary canal; the legs are curious, being very Dale and nearly transparent. These caterpillars e full grown in June.

AT a recent meeting of the Institution of Civil

The improvements described in the paper were based upon Mr. Siemens' regenerative furnace. Each stove of a pair consisted of a wrought-iron cylindrical casing, lined with fire-brick, and provided with a central shaft or flue, which extended to within a few feet of the brick dome forming the top. Around this shaft there were a number of compartments, or boxes, formed of bricks so placed that those in one course were not exactly coincident in position with those in the courses either above or below, though a passage was left open from the bottom to the top of the mass of brickwork. This wrought iron casing was provided with several valves, three being for the admission of cold blast, of gas, and of air for combustion, and two being for the exit of the hot blast and of the products of combustion. When a stove had been at work heating blast, and it was wanted to re-heat it, the first thing to be done was to put another stove in operation, then to shut the hot and the cold blast valves, allowing the air in the stove to be blown out at a small valve to reduce it to atmospheric pressure. The gas, air, and chimney valves were next opened, and the gas, igniting as it entered, gave a large volume of flame right up the central shaft and over and into the regenerator, thus heating the top course of brickwork considerably, the next course rather less, and so on, the products of combustion passing away to the chimney at a temperature of about 300 deg. In the course of a few hours, a large amount of caloric was stored up in the bricks forming the regenerator, a good red heat penetrating nearly to the bottom, when the stove was again ready to heat the blast to a temperature of 1400 deg. or 1500 deg. In these stoves the cost of dust catchers was avoided, and the expense of producing gas was also saved, as the gas was used direct from the top of the blast furnace, and the stoves could be cleaned out with the greatest facility. The construction of the regenerator in compartments or boxes, connected together vertically but not horizontally gave the power of applying the blast with efficiency (inasmuch as the whole force of the blast was confined to the one passage that was being blown at the time), and admitted of a brush being passed up or down the boxes to remove the dust. The form and proportion of the passages had been found, after numerous experiments to produce an excellent effect in mixing the air, thereby ensuring a rapid and perfect conduction of heat from the brick to the air, or vice versa, from the products of combustion to the bricks.

The results obtained by Messrs. Cochrane from the adoption of these stoves at Ormesby, as regarded the quality of iron, the increased make, and the saving of coke in the blast furnace, had been most satisfactory. Thus there was a saving of 4 cwt. of coke per ton of iron produced, by the use of the regenerative stoves for heating the blast, when compared with good cast-iron pipe With a large furnace, stoves, and the saving was still more ordinary pipe stoves. producing 475 tons & week, the first cost of these stoves was somewhat less than the cost of pipe stoves, while the expense of working was less, so that the profit, taking every thing into account was estimated to amount to about £4162 a Year.

[graphic]

BARNACLES.

over

WE give this week an engraving of a group of

tion.

barnacles-a most accurate representa

It requires a good deal of faith to believe that barnacles are related to crabs, for they are not the least alike, and the first is fixed like a shell-fish

on to pieces of timber floating about in the sea, or Engineers a paper read was " On Recent Im-to the rocks washed by the tide; while the last provements in Regenerative Hot-blast Stoves for Blast Furnaces," by Mr. E. A. Cowper.

has legs, claws, eyes, and the power of moving and swimming. Yet it is quite true that the

F

BARNACLES.

barnacle belongs to the same class of animals that legs close to its head, and a large tail; it has includes the crabs, shrimps, and lobsters. If a eyes, and swims about most vigorously. It appiece of rock is put into a large glass full of sea pears to be constantly in movement, and although water, many things may be seen on it which are actively employed in swimming, and in crawling, of a white colour, and whose shape is something it does not care to seek for food. After a while like that of a thimble with the top battered in. If the young free-swimming creature rests upon a they are examined it becomes evident that the piece of rock, or wood, or even on the back of a conical outside is formed of several little bits of fish, and then a wonderful alteration takes place, hard shell joined together very carefully, and The long legs and feelers near the head grasp the that the top has a valve in it. When the water is substance on which the creature is to live for the quite clear and quiet, a small flapper is forked out future, and a gummy substance comes from a through the valve, and is moved to and fro with a gland which has been growing for some time close motion like that of opening and shutting the fin- to the head. The gum sticks the legs and the gers. The flapper has some long bristles attached feelers to the substance, the eyes diminish in size to it, and they are beautiful, feathery-looking and are no longer seen, the tail and the hind legs things when examined under a microscope. The grow into the feathery flappers already noticed movement goes on for hours, and ceases upon the and the shell of many pieces encloses all. The least alarm. Then the flappers are withdrawn, barnacle is then fixed for life, head downwards, the valve closes, and the barnacle-for such is the and it loses its organs of sight, and receives a creature-looks again like a conical piece of stone mouth and stomach, which it had not before, when The Happers are the lungs as well as the hands of in the free-swimming state. All barnacles do not the barnacle, and minute living creatures are en- undergo this change, for the males of some kinds tangled by them and passed by a current of water live inside the conical house which holds the into the mouth, which is within the shell. When female, and never have houses of their own, for the barnacle produces its eggs, it ejects them with they remain in the free-swimming state. All the a stream of water, and they float about in the sea, animals of the crab class have to undergo a change being very minute things. They soon become of form before arriving at maturity, and the comhatched, and then it is that the reason becomes mon shore crab, when it is first hatched, is a long clear why barnacles and crabs are placed by thing with a great head, and legs fitted for swimzoologists in the same class. The young barnacle ming, and not for crawling. As it grows the body is just like a shrimp, with a glong body, many long shortens by curling the tail end underneath, and

the legs and claws grow out of the swimming apparatus. Some of the barnacles that live on coral reefs are very beautiful, and their shells are ornamented in imitation of the flower-like polypes of the stony madre pores.

The accompanying illustration will give the reader a good idea of the appearance which a family of barnacles presents, clinging to the under surface of a floating log.-Scientific American.

[graphic]

NOTES ON RECENT DISCOVERIES IN
SCIENCE, AND THEIR PRACTICAL AP-
PLICATIONS.*

POISONOUS PROPERTIES OF NEW DYES.

A Step has reputedly poisonous

FURTHER step has been made in the in

properties of some of the new dyes. There can be no doubt that cases have occurred in which intensely irritating effects have been produced by a few of these colours, but they have been rare relatively to the frequent use of articles, such as stockings, dyed with them. The researches of M. Guyot go to show that these dyes are poisonous or not according as they are pure or impure. Thus, it is said that azuline, the blue, is poisonous if it contains an excess of aniline. The same colour also produces irritation of the skin when prepared with coraline containing excess of phenol. The coraline red, as we have mentioned before, is the colour which in most cases produced the effects which caused the alarm on the subject. It is not necessary to say more on the matter, for, as the manufacture of the dyes improve, the effects now seen but rarely will never be observed.

ELECTROLYSIS OF NITRIC ACID.

When a very dilute acid is operated upon, hydrogen only is evolved at the negative pole, and no secondary product is found in the liquid contained in the negative compartment. With a less dilute acid, that is, an acid with about 125 equivalents of water, hydrogen is first given off, then a little nitrogen, and the liquid is found to contain traces of ammonia. In the case of a stronger acid with only 15 equivalents of water, while oxygen is freely given off at the positive pole, no hydrogen for some time escapes at the negative, all that gas re-acting on and combining with the acid in the compartment, the liquid assuming a distinctly blue colour. After some time, however, hydrogen mixed with some nitrogen comes off, but soon gives place to an evolution of binoxide of nitrogen which in its turn ceases, and hydrogen again appears. In the end a good deal of ammonia is found in the negative liquid, and also much nitrious acid. Nitric acid with two equivalents of water gives off at first only binoxide of nitrogen, then hydrogen. Thus we see that the reducing action of hydrogen on nitric acid, according to the strength of that acid, produces nitrous acid, binoxide of nitrogen, nitrogen, and ammonia.

LOGWOOD IN WINE.

A very easy way of detecting logwood colour in wine has been published in France, which, if good for anything, will be useful in discovering the adulteration of port. We have only to moisten a acetate of copper, and dip it into the suspected strip of paper with a strong solution of neutral vinous fluid, which, if it contains logwood, will give a blue colour to the paper. If, however, the colour of the wine be the natural product of the grape the paper changes to a grey shade.

TENSION OF LIQUIDS.

An observation has been made which has resulted in the discovery of a new mode of estimating the strength of alcohol. M. Ducaux has been experimenting on the superficial tension of liquids with an apparatus which exhibits the variations of it in a very remarkable way. A dropping tube, for instance, is arranged to let fall in air 100 drops a minute. If, now, the experiment be repeated in air saturated with vapour of alcohol, instead of 100 drops, 110 will fall in the minute. This is water, by which the superficial tension of th caused by the solution of some alcohol in th liquid is diminished. Further experiments led t the discovery that the strength of alcohol could be exactly determined by ascertaining how many drops would fall in a minute from a given orifice.

TO DYE LINEN WITH ANILINE BLACK.
A simple process is given in the German Dyers
Journal, which is said to produce a very deep and
beautiful black on linen goods by means of ani-

*From the Mechanics' Magazine.

TO DETECT THE ADULTERATION OF RICE FLOUR.

out blackening, remaining brilliant to the last. M. Morren tells us further the diamonds have different crystalline structures, revealed by the appearance of half-burnt specimens.

A MODIFICATION OF SMEE'S GALVANIC
BATTERY.

line. The goods are first immersed in a bath consisting of a solution of acetate of aniline of 4 deg. Baume, to which is also added 4 per cent, of sal ammoniac, 4 per cent. of chlorate of potash, per cent. of nitric acid, and 1 per cent. of sulphate of copper. The goods are then wrung out, and are taken moist to an oxidising chamber and exposed to moist warm air. After two or three days the A Frenchman, M. Figuier, has succeeded in black is fully developed, and the goods only re-producing, but with considerable trouble, a cheap quire to be rinsed in a weak solution of ammonia, battery on the same principle as Smee's. Instead and finally in weak soap and water. The result of a simple platinum plate he makes plates of is said to be an extraordinarily beautiful colour. retort coke, paints them over with a strong solution of chloride of platinum, dries and then reduces the metal upon the coke by heating it in the fire. Silvered carbon may, however, be used, Rice flour is said to be often adulterated with instead of platinised, but these plates are obtained wheaten, rye, and maize flour, as well as cheaper with more trouble. The carbons are first done materials. The detection of these depends upon over with a solution of nitrate of silver, and are the recognition of cerealine, or, if pea or some then, while moist, exposed to hydrochloric acid other meals have been used, leguminosin. Picric gas. In this way, a coating of chloride of silver acid has the property of precipitating these sub-is procured which may be fused into the coke by stances, and thus becomes an important agent heating. The silver will be reduced upon the in the detection of the above adulterations. It is carbon by the first action of the battery. Plates employed in the following way:-The suspected made in either of these ways, M. Figuier says, are flour is first digested with cold water for an hour superior to the platinised silver or platinum plates or two, the mixture being frequently stirred. Then hitherto used in a Smee's battery, the irregular the liquor is quickly filtered, and the filtrate is surface promoting the escape of the hydrogen. gradually mixed with about an equal volume of a The author details a method of giving a rough cold saturated solution of picric acid. Any pre- surface to the cut plates of retort coke. It consists cipitate produced shows that the rice flour has in spreading the plates over with a mixture of dibeen adulterated with one of the above-named luted white of egg or blood albumen and syrup, substances. Two per cent. of most of them may and then carefully burning them until smoke is no be detected in this way. longer given off. The process being repeated two or three times, myriads of points, the débris of minute vesicles, remain firmly attached to the original carbon plate. The plates thus made must be well washed in a large quantity of water, to remove any loose particles which might otherwise fix themselves accidentally upon the zinc, and set up local action. These carbon plates are very durable, the author having had some in use for three years. They are comparatively cheap if troublesome to make, and the simplicity of the arrangement of the battery will, no doubt, recommeud this modification.

A USEFUL CEMENT.

We mentioned a year or two ago that an excellent cement for fixing iron or stone was made by mixing together commercial glycerine and ground litharge. To-day we read of many other applications of this compound, which seems to be extremely useful. As a cement for joining chemical apparatus, it offers many advantages, for it is unaffected by chlorine, hydrochloric acid, sulphur vapour, sulphurous acid, nitric acid, and, indeed, resists most corrosive vapours. Further than this, it withstands the solvent action of alcohol, ether, sulphide of carbon, and all hy. drocarbon vapours. It hardens in from ten to

NE

STAR-MIST.*

lectively the diffused light which forms the Milky Way.

Sir John Herschel, applying a similar series of researches to the southern heavens, was led to a very similar conclusion, His view of the sidereal system differs chiefly in this respect from his father's, that he considered the stars within certain limits of distance from the sun to be spread less richly through space than those whose united lustre produces the milky light of the galaxy.

Now it is clear that if the supposition on which these views are based is just, the three following results are to be looked for.

In the first place the stars visible to the naked eye would be distributed with a certain general uniformity over the celestial sphere; so that if on the contrary we find certain extensive regions over which such stars are strewn much more richly than over the rest of the heavens, we must abandon Sir Wm. Herschel's fundamental hypothesis, and all the conclusions which have been based upon it.

In the second place, we ought to find no signs of the aggregation of lucid stars into streams or clustering groups. If we should find such associated groups we must abandon the hypothesis of uniform distribution, and all the conclusions founded on it.

Thirdly, and most obviously of all, the lucid stars ought not to be associated in a marked manner with the figure of the Milky Way. To take an illustrative instance. When we look through a glass window at a distant landscape, we do not find that the specks in the substance of the glass seem to follow the outline of valleys, hills, trees, or whatever features the landscape may present. In like manner, regarding the sphere of the lucid stars as in a sense the window through which we view the Milky Way, we ought not to find these stars, which are so near to us, associated with the figure of the Milky Way, whose light comes from distances so enormously exceeding those which separate us from the lucid stars. Here again, then, if there should appear signs of such association, we must abandon the theory that the sidereal system is constituted as Sir Wm. Herschel supposed.

It should further be remarked that the three arguments derived from these relations are independent of each other. They are not as three triple cord. If one strand holde, the cord holds. the chain is broken. They are as three strands of links of a chain, any one of which being broken It may be shown that all three are to be trusted. It is not to be expected, however, that the stars

thirty minutes if mixed of the consistence of ON STAR-GROUPING, STAR-DRIFT, AND a thick dough, and sets under water as quickly as in air. Moreover, it will stand a very much higher temperature than any oil cement. The composition may be also employed for moulds for electrotyping. For this purpose glycerine must be stirred with the litharge until a mixture of the proper consistence is obtained. The article to be copied must be smeared with dilute glycerine before the mix- indeed in our own, very little was certainly known as actually seen should exhibit these relations,

ture is poured on, and plenty of time must be given for it to set.

ACTION OF HEAT ON DIAMONDS.

A jeweller at Marseilles had a couple of diamond shirt studs sent to him for the purpose of

EARLY a century has passed since the known-the Newton of observational astronomy; greatest astronomer the world has ever as he has justly been called by Arago-conceived the daring thought that he would gange the celestial depths. And because in his day, as

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visible; so that the eye would look in vain for since far the larger number are but faintly the signs of law among them, even though law may be there. What is necessary is that maps sbould be constructed on a uniform and intelligible plan, and that in these maps the faint

having the gold setting enamelled. Not being is my purpose to attempt to prove that-as Sir stars should be made bright, and the bright stars

brighter.

respecting the distribution of the stars, he was forced to found his researches upon a guess. supposed that the stars, not only those visible to the naked eye, but all that are seen in the most powerful telescopes, are suns, distributed with a certain general uniformity throughout space. able to remove easily the stones from the setting Wm. Herschel was himself led to suspect during he determined to leave them. Not having any the progress of his researches this guess was a charcoal, moreover, he heated his muffle furnace mistaken one; that but a small proportion of the with coal. When the studs were taken from the stars can be regarded as real suns; and that in There are twelve of them, but they overlap, so muffle he found that the enamel was perfect, but to his surprise the diamonds were black. Vain place of the uniformity of distribution conceived were his endeavours to restore the brilliancy of by Sir Wm. Herschel, the chief characteristic of the stones. Rubbing only made them shine like the sidereal system is infinite variety.

been devised for this purpose amongst others. The maps exhibited during this discourse have

that in effect each covers a tenth part of the heavens, There is first a north-polar map, then five maps symmetrically placed around it; again, there is a south-polar map, and five maps symso fit in with the first five as to complete the enclosure of the whole sphere. In effect every map of the twelve has five maps symmetrically placed around it and overlapping it."

In order that the arguments on which these black lead. The stone of the lapidary, however, views are based may be clearly apprehended, it metrically placed round that map; and these five

cut away the black layer, and then it was found that the weight of the stone had not been diminished. This curious result induced M. Morren

to make some experiments on the behaviour of diamonds exposed to heat under different condi

will be necessary to recall the main results of Sir Wm. Herschel's system of star-grouping. different parts of the heavens, he counted the stars Directing one of his 20-feet reflectors to seen in the field of view. Assuming that the

tions. First, he heated one to a white heat in a telescope really reached the limits of the sidereal visible to the naked eye, each of the maps should

Since the whole heavens contain but 5932 stars contain on the average about 593 stars. But instead of this being the case, some of the maps

current of coal gas, and obtained exactly the same result as the jeweller. The stone appeared to be system, it is clear that the number of stars seen in any direction affords a means of estimating the covered with a layer of plumbago, which could relative extension of the system in that direction,/ contain many more than their just proportion of

provided always that the stars are really distributed throughout the system with a certain approach to uniformity. Where many stars are seen, there the system has its greatest extension; where few, the limits of extension must be nearest to us.

not be removed by friction, and the stones were found to have increased in weight. M. Morren succeeded in burping the black deposit away by simply heating the stone to redness in the air, after which it was as brilliant as before. Heated in hydrogen the diamond remains completely unaffected, even at the temperature at which platiSir Wm. Herschel was led by this process of num melts. In carbonic acid, however, it loses brilliancy and also weight if the exposure to heat star-grouping to the conclusion that the sidereal is prolonged. M. Morren tells us that it is often system has the figure of a cloven disc. The stars visible to the naked eye lie far within the limits difficult to burn diamonds, which is a matter of of this disc. Stars outside the relatively narrow little consequence, since it is what people seldom wish to do. If anyone. however, desires to in-limits of the sphere, including all the visible stars, dulge in the expensive amusement he may be has its greatest extension these orbs produce colare separately invisible; but where the system glad to know that in most cases it is sufficient to make the stone white hot on platinum, and plunge into oxygen, when it is quietly consumed with

*The substance of a lecture delivered by R. A. PROCTOR, B.A., at the Royal Institution on May 6.

stars, while in others the number as greatly falls short of the average. One recognises, by combining these indications, the existence of a roughly circular region, rich in stars, in the northern heavens, and of another, larger and richer, in the southern hemisphere.

To show the influence of these rich regions, it is only necessary to exhibit the numerical relations presented by the maps.

of the northern rich regions fall, contains no less The north-polar map, in which the largest part than 693 lucid stars, of which upwards of 400 fall within the half corresponding to the rich region.

It will be understood that the description here, and all which immediately follows, replaces portions of the discourse which would only be intelligible when illustrated by means of the diagrams and illuminated maps actually employed.

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It is wholly impossible not to recognise so unequal a distribution as exhibiting the existence of special laws of stellar aggregation.

In the first place the mere amount of a star's apparent motion must be regarded as affording a means of estimating the star's distance. The nearer a moving object is, the faster it will seem to move, and vice versa. Of course in individual instances little reliance can be placed on this indication; but by taking the average proper motions of a set of stars, no untrustworthy measure may be obtained of their average distance, as compared with the average distance of another set.

variety of structure, and special laws of distribu-motion among the stars, but he did not interpret
tion within the sidereal system.
this as I do. He had formed the idea that the
whole of the sidereal system must be in motion
around some central point; and for reasons
which need not here be touched on, he was led to
believe that in whatever direction the centre of
motion may lie, the stars seen in that general
direction would exhibit a community of motion.
Then, that he might not have to examine the
proper motions all over the heavens, he inquired
in what direction (in all probability) the centre of
motion may be supposed to lie. Coming to the
conclusion that it must be towards Taurus, he exa-
mined the proper motions in that constellation, and
found a community of motion which led him to re-
gard Alcyone, the chief star of the Pleiades, as
the centre around which the sidereal system is
moving. Had he examined farther he would have
found more marked instances of community of
motion in other parts of the heavens, a circum-
stance which would have at once compelled him
to abandon his hypothesis of a central sun in the
Pleiades, or at least to lay no stress on the evidence
derivable from the community of motion in
Taurus.

It is noteworthy, too, that the greater Magel-
lanic cloud falls in the heart of the southern rich For example, we have in this process the means
region. Were there not other signs that this of settling the question whether the apparent
wonderful object is really associated with the brightness of a star is indeed a test of relative
sidereal system it might be rash to recognise this nearness. According to accepted theories the
relation as indicating the existence of a physical sixth-magnitude stars are ten or twelve times as
connection between the Nubecula Major and the far off as those of the first magnitude. Hence
southern region rich in stars. Astronomers have their motions should, on the average, be corre-
indeed so long regarded the Nubeculae as belong-spondingly small. Now, to make assurance
ing neither to the sidereal nor to the nebular doubly sure, I divided the stars into two sets, the
systems, that they are not likely to recognise very first including the stars of the 1st, 2nd, and 3rd,
readily the existence of any such connection. Yet the second including those of the 4th, 5th, and
how strangely perverse is the reasoning which 6th magnitude. According to accepted views, the
has led astronomers so to regard these amazing average proper motion for the first set should be
objects. Presented fairly, that evidence amounts about five times as great as that of the second. I
simply to this:-The Magellanic clouds contain was prepared to find it about as three times as
stars and they contain nebula; therefore they are great; that is, not so much greater as the accepted
neither nebular nor stellar. Can perversity of theories require, but still considerably greater. To
reasoning be pushed farther? Is not the obvious my surprise I found that the average proper
conclusion this, that since nebulæ and stars are motion of the brighter orders of stars is barely
seen to be intermixed in the Nubeculæ, the equal to that of the three lower orders.
nebular and stellar systems form in reality but
one complex system.

As to the existence of star-streams and clustering aggregations, we have also evidence of a decisive character.* There is a well-marked stream of stars running from near Capella towards Monoceros. Beyond this lies a long dark rift altogether bare of lucid orbs, beyond which again lies an extensive range of stars, covering Gemini, Cancer, and the southern parts of Leo. This vast system of stars resembles a gigantic sidereal billow flowing towards the Milky Way as towards some mighty shore-line. Nor is this description altogether fanciful; since one of the most marked instances of star-drift presently to be adduced refers to this very region. These associated stars are urging their way towards the galaxy, and that at a rate which, though seemingly slow when viewed from beyond so enormous a gap as separates us from this system, must in reality be estimated by millions of uniles in every year.

Other streams and clustering aggregations there
are which need not here be specially described.
But it is worth noticing that all the well-marked
streams recognised by the ancients seem closely
associated with the southern rich region already
referred to. This is true of the stars forming the
River Eridanus, the serpent Hydra, and the
streams from the water-can of Aquarius. It is
also noteworthy that in each instance a portion of
the stream lies outside the rich region, the rest
within it; while all the streams which lie on the
same side of the galaxy tend towards the two
Magellanic clouds.

Most intimate signs of association between
lucid stars and the galaxy can be recognised,-
(i.) in the part extending from Cygnus to Aquila;
(ii) in the part from Perseus to Monoceros
(iii) over the ship Argo; and (iv.) near Crux and

the feet of Centaurus.

Before proceeding to the subject of Star-drift, three broad facts may be stated. They are, I believe, now recognised for the first time, and seem decisive of the existence of special laws of distribution among the stars:

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First, the rich southern region, thongh covering
but a sixth part of the heavens, contains one-third
of all the lucid stars, leaving only two-thirds for
the remaining five-sixths of the heavens.
Secondly, if the two rich regions and the Milky
Way be considered as one part of the heavens,
the rest as another, then the former part is three
times as richly strewn with lucid stars as the

second.

This proves beyond all possibility of question that by far the greater number of the fainter orders of stars (I refer here throughout to lucid stars) owe their faintness not to vastness of distance, but to real relative minuteness.

To pass over a number of other modes of research, the actual mapping of the stellar motions, and the discovery of the peculiarity to which I have given the name of star-drift, remains to be considered.

In catalogues it is not easy to recognise any instances of community of motion which may exist among the stars, owing to the method in which the stars are arranged. What is wanted in this case (as in many others which yet remain to be dealt with) is the adoption of a plan by which such relations may be rendered obvious to the eye. The plan I adopted was to attach to each star in my maps a small arrow, indicating the amount and direction of that star's apparent motion in 36,000 years (the time-interval being purposely lengthened, as otherwise most of the arrows would have been too small to be recognised). When this was done, several well-marked instances of community of motion could immediately be recognised.

Perhaps the most remarkable instance of stardrift is that observed in the constellations Gemini and Cancer. Here the stars seem to set bodily towards the neighbouring part of the Milky Way. The general drift in that direction is too marked, and affects too many stars, to be regarded as by any possibility referable to accidental coincidence. It is worthy of note that if the community of star-drift should be recognised (or I prefer to say, when it is recognised), astronomers will have the means of determining the relative distances of the stars of a drifting system. For differences in the apparent direction and amount of motion can be due but to differences of distance and position, and the determination of these differences becomes merely a question of perspective.*

Before long it is likely that the theory of stardrift will be subjected to a crucial test, since spectroscopic analysis affords the means of determining the stellar motions of recess or approach. The task is a very difficult one, but astronomers have full confidence that in the able hands of Mr. Huggins it will be successfully accomplished. I await the result with full confidence that it will confirm my views.

(To be concluded next week.)

MECHANICAL MOVEMENTS. (Continued from page 221.) ta t'

Connecessary to premise, however, that before 119 Compensation balance, a is the

the experiment was tried, there were reasons for
feeling very doubtful whether it would succeed.
A system of stars might really be drifting athwart
the heavens, and yet the drift might be rendered
unrecognisable through the intermixture of more
distant or nearer systems having motions of
another sort, and seen accidentally in the same
general direction.

screws for regulation at the ends. t and tare two compound bars, of which the outside is brass and the inside steel, carrying weights b b. As heat increases, these bars are bent inward by the greater expansion of the brass, and the weights are thus drawn inward, diminishing the inertia of the balance. As the heat diminishes, an opposite effect is produced. This balance compensates both for its own expansion and contraction, and that of the balance-spring.

This was found to be the case, indeed, in several instances. Thus the stars in the constellation Ursa Major, and neighbouring stars in Draco, 120. Endless chain, maintaining power on exhibit two well-marked directions of drift. The going-barrel, to keep a clock going while winding, stars B, y, d, e, and of the Great Bear, besides during which operation the action of the weight two companions of the last-named star, are tra- or main-spring is taken off the barrel. The wheel velling in one direction, with equal velocity, and to the right is the "going-wheel," and that to the clearly form one system. The remaining stars in left the "striking-wheel." P is a pulley fixed to the neighbourhood are travelling in a direction the great wheel of the going part, and roughened, almost exactly the reverse. But even this relation, to prevent a rope or chain hung over it from thus recognised in a region of diverse motions, is slipping. A similar pulley rides on another arbor full of interest. Byron Madler, the celebrated p which may be the arbor of the great wheel German astronomer, recognising the community of the striking part, and attached by a ratchet of motion between Ursa and its companions, and click to that wheel, or to clock-frame, if there calculated the cyclic revolution of the system to be is no striking part. The weights are hung, as may certainly not less than 7000 years. But when be seen, the small one being only large enough to the complete system of stars showing this motion keep the rope or chain on the pulleys. If the part is considered, we get a cyclic period so enormous, b of the rope or chain is pulled down, the ratchet that not only the life of man, but the life of the pulley runs under the click, and the great weight is pulled up by e without taking its pressure off the existence of the solar system, must be regarded the going-wheel at all. as a mere day in comparison with that amazing

Thirdly, the southern hemisphere contains one human race, the existence of our earth, nay, even

thousand more lucid stars than the northern, a
fact which cannot but be regarded as most
striking when it is remembered that the total cycle.
number of lucid stars in both hemispheres falls
short of 6000.

Two or three years ago, the idea suggested it-
self to me that if the proper motions of the stars
were examined, they would be found to convey
clear information respecting the existence of

Here, again, without the illustrative maps the argument is necessarily rendered imperfect.

Then there are other instances of star-drift where, though two directions of motion are not intermixed, the drift character of the motion is not at once recognised, because of the various distances at which the associated stars lie from the eye.

121. Harrison's "going-barrel." Larger ratchet-wheel, to which the click Ris attached, is connected with the great wheel G by a spring S S'. While the clock is going, the weight acts upon the great wheel G through the spring; but as soon as the weight is taken off by winding, the

* Here no account is taken of the motions of the stars A case of this kind is to be met with in the with the conimon motion of the system. within the system; such motions must be minute compared stars forming the constellation Taurus. It was here that Mädler recognised a community of Editor of the American Artisan. + Extracted from a compilation by Mr. H. T. Brown

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