The English Mechanic AND that the average number of meteors which daily the solar system. But there might be the end of enter the earth's atmosphere is about 400,000,000, the matter-a family of meteor systems would be though of these only 7,500,000 are such as can found to exist somewhat resembling in distribube seen by the naked eye. Now the earth tion the family of the asteroid outside the orbit of Mars. MIRROR OF SCIENCE AND ART. occupies, as we know, about 3654 days in circling COMETS AND METEORS. By RICHARD around the sun, therefore she encounters in the WHEN, more than two centuries ago, Kepler tant of meteors; for it must be remembered asserted that there are more comets in the universe than there are fishes in the ocean, he was laughed at as a theorist. Yet the assertion was founded on sufficient evidence-it was, indeed, founded on evidence which, paradoxical as it may sound, is not simply probable, but absolutely certain Infinitely more wonderful, however, are the conclusions to be drawn from the observed relations of the meteoric systems. (To be continued.) THE WORLD, ITS FORMATION AND the evidence from probability. He saw that the the earth's weight increases yearly by 146,100,000 T chances against the detection, by us, of any comet, supposed to be selected at random from the hosts which people space are so enormous that for every single comet we recognise there must be millions which escape our observation. Therefore he argued conclusively (only the men of his day could not see the force of the argument), that since many comets have been discovered, untold millions must exist throughout space. We now know that the illustrious German was right-nay, we know that the theory which seemed to his contemporaries so startling, fell very far short of the truth. For he only knew of those bright comets which are palpable to ordinary vision. He had no reason to believe that for every large comet there are myriads of smaller ones-that is, of comets not merely inferior in apparent size and brilliancy, but in reality minute by comparison. BY ARTHUR UNDERHILL that only a very small proportion of them can Were it otherwise Let it be remembered that though these results are so far doubtful that we have deduced them in ignorance of the actual average weight of the meteors our earth encounters, yet no doubt whatever rests on the conclusion that each year the earth grows many hundreds of tons heavier by the continual fall of meteoric substance upon her surface. But now we have to inquire whether the ring round which the earth travels is the only part of the solar system which is thus peopled by meteors. Such a conclusion seems in itself altoether unlikely, but yet the consequences which follow fromsupposing any very large proportion of the sphere ruled over by the sun to be thus peopled, are so astonishing that we may well require very clear evidence before admitting that this supposition is just. Certain peculiarities of meteoric motion serve conclusively to establish the thesis that our earth's orbit is by no means exceptionally thronged with meteors. Those peculiarities I shall indicate somewhat briefly, premising that the evidence we have on the matter is absolutely beyond question. Now I propose to exhibit the really startling conclusions which may be drawn from what we know of the cometic and meteoric system within the solar scheme, these conclusions being not hypothetical, as they might be thought on a first view, but as legitimately inferrable from the evidence as Kepler's daring proposition respecting the comets which people space. I propose to show that the solar system is full of comets and meteors-in this sense, that though the combined volume of all the cometic or meteoric substance existing in any given space within the solar system may be almost indefinitely minute, yet that no considerable space (no space so large perhaps, as the moon's globe), exists without some such substance within it. I wish it to be particularly understood that I am not about to theorise. I propose only to pass by legitimate inferences from the known and unknown, and I shall be especially careful to distinguish what is doubtful, or at least not absolutely certain, from that which must be held by all who understand the laws of probability to be thoroughly established by the evidence. Let us picture our earth circling on her wide orbit around the sun. That orbit has a diameter of about 180 millions of miles, and therefore the space through which the earth actually sweeps on her course round the sun must be regarded as being (relatively to him) a ring of cross-section equal to the earth's. We know what the actual volume of that ring must be; it is, in fact, equal to the volume of a circular cylinder nearly 8000 miles in diameter, and equal in height to the circumference of the earth's orbit. But the real One thing, then, has become very obvious. volume of the ring does not at present concern us. The whole of any such system, except the part Now in sweeping onwards upon her orbit, the crossed by the earth (a mere line through the earth encounters a multitude of meteoric sub- system one may almost say-since the earth's stances, of different size and weight, some ex- diameter is as nothing in such a relation), passes ceedingly minute no doubt, others a very few-altogether clear of the earth's orbit. We must weighing many hundredweights or even tons. This particular ring of space within the solar system is peopled, then, with meteoric bodies. This fact is beyond all question. Let us, inquire, however, how many meteors may be supposed to be within the ring at any moment, then afterwards proceeding to inquire whence they came and whither they go, as also according to what laws they are associated with each other and with other bodies, we shall find conclusions of a somewhat surprising character flowing from this first simple relation. It has been calculated by Prefessor Newton* The results of this calculation are quoted in Mr. Lockyer's "Elementary Lessons in Astronomy;" but with a remissness, somewhat too common in that compilation, they are not referred to their author. It cannot be too often insisted upon that not courtesy alone, but common justice requires that all special results of this sort should be distinctly assigned to him who has been at the pains to calculate them. most science in a more practical light, and who look rather to the utility, than to the philosophy of knowledge, geology ought, to be entertaining. Its great use in engineering, mining, and agriculture, must recommend it to them. To the artist, it cannot fail to be of interest, diversifying as it does so greatly the scenery of the globe. To the architect, the facility of obtaining stone for his building presents itself as an element in the conception of his design, and by a slight knowledge of geology, he is enabled to tell what particular kind of material he will find upon, or near his site, and so choose that which, with an equal appearance and durability, may be most easily obtained. Seeing, then, how pleasant and useful is the cultivation of this branch of natural knowledge, I think it requires nothing more from me to show that its elements deserve the perusal of all who are in any way interested in science, and I shall therefore without further preface proceed to my task. In the first place, there are certain parts of her path where the earth encounters more meteors Looking at the earth as it now is, we see that than elsewhere. Picturing her as she swiftly it is greatly diversified by hills and vales, mountravels round the sun, we have to conceive the tains and plains, whose firm and solid appearance existence along certain parts of her path, of richer impress us at first sight with the idea that they aggregations of meteors than exist elsewhere. Now, were co-existent with the creation of the world. if it were possible for an aggregation of meteors Such is not, however, the case. The loftiest Alpine to stay in a certain definite part of the solar peak, whose snow-capped summits now rises system, we should not learn much from the pe- proudly above the clouds, was once sunk culiarity here considered. But there is no such fathoms deep beneath the ocean, and the quiet thing as rest under the influence of the sun's secluded dell did not always enjoy its present tremendous attractive energies. Those aggre- state of humble repose. Change, ceaseless, and gations, if initially at rest, would in no brief in some cases so slow as to be scarcely percep space fall in upon the sun's surface. The tible in a century, has been, and is even now fact, then, that year after year, as the earth re-altering the face of the earth; here, by means of turns to the same part of her orbit, she either always, or commonly, shows that there must be a system travelling round the sun, and intersecting the earth's orbit in that particular region. therefore add to the conceptions we have already Mentioning, in passing, that 56 such systems Yet, after all, these systems might all have orbits, so closely, approaching the earth's orbit in figure and position as to render their actual intersection by the earth's orbit no very striking circumstance. It would remain, of course, abun dantly wonderful that so many meteoric orbits crowded along a greater or less portion of their extent with discrete masses should exist within the untiring sea, wearing away the isthmus of hard granite and finally cutting a channel through it; there upheaving the land by earthquakes, and volcanic agency and erecting new islands-aye, in some cases even continents where formerly was a mere waste of water, and throwing up the plain into the most rugged and picturesque mountain ranges. At one place by the aid of the tornado drifting huge masses of sand over the country, and converting the fruitful land into a sterile desert; at another, deep buried in the earth, forming those mineral treasures which are so useful to man. Even the smallest of created beings helps to push on this ceaseless mutation, and the coral insect whilst building its own habitation forms a foundation for that of man. We find, then, that geological change is due to five agencies-namely, the aqueous, the igneous, the atmospheric, the chemical, and the organic. (or that caused by animal or vegetable life). Geological research is necessarily confined to the upper crust or shell of the globe, as it is impossible to penetrate more than some two or three miles below the surface, and only that far through the help of landslips and upheavals of the crust by igneous agency. I must here premise that the sense in which the term "Rock" is used by geologists is different to that which is popularly ascribed to it. By "rock," in this treatise, will be meant every kind of formation which enters into the composition TRAP ROCK is a hard dark formation, geneof the crust of the globe; thus, soil, sand, clay,rally found arranged in a series of steps, or &c., are, geologically speaking, rocks, although terraces. they are not indurated or stony. If we could cut a huge wedge-like slice out of the earth, we should find that the sides of the dyke or valley this formed would be arranged in a series of layers, or bands of different kinds of rock; these layers are called strata, and those rocks which are always found thus arranged are called stratified, aqueous, or sedimentary rocks. Perhaps, however, we might find a place in our valley where another species of rock had forced its way upwards, upheaving the strata, and in some parts breaking through it, and inclining it at all angles to its previous condition, as in Fig. 1, where the parallel lines are the stratified world. (To be continued.) ANCIENT COINS.-IV. N N the 23rd of May, and the three following days, a very valuable collection of ancient coins and medallions was dispersed under the hammer of Messrs. Sotheby, Wilkinson, and Hodge, in Wellington-street, S rand. It was the property of Mr. Jules Sambon, of Naples, and realised a very large sum. We intend to select from this sale the most important specimens, and give their prices, with remarks and descriptions, in order that the collector may form some idea of the present value of the rarer coins in the several series. In the following list the terms "patina" and "patinated" very frequently occur. We think that they may be best explained in the words of Pinkerton:-"Nothing contributes so much to the conservation of brass or copper coins as that fine rust, appearing like varnish, which their lying in a particular soil occasions. space in the centre of a coin where no figure is placed. With these explanations, which are intended only for the beginner, we will now commence our lists. Lots 1 to 31 were the bronze cast coins of ne Græco-Italian cities of Etruria, Umbria, Picenurn, and Latium. They consisted of ases, and divisions of the as. (Explained in our second article, on page 197.) Obv., HAT., head issuing from a shell. Rev., a Lot 7. Picenum, Hatria or Hadria, Quincunx pegasus flying to the right. Exquisitely preserved and patinated, and of great rarity; size, 16. £11. 15. Latium.-As. Obv., beardless head with Phrygian helmet. Rev., same head. Very fine; size, 17. £6 10s. 31. Latium.-As. Obv., helmeted head of Pallas, full-faced. Rev., bull standing to left, caduceus beneath, and ROMA in the exergue. Size, 19. Another similar, but with L under the bull. These two pieces, the only two varieties known, were purchased of the Roman dealer Depoletti, who obtained them from the renowned find of Vicarello. The one with the caduceus is in first-rate preservation-the finest coin of the find; the other is not quite so perfect. The great value of all these Italic coins, when fine, is well known. £30 (Bunbury). Lots 32 to 34 were bronze coins of Apul Luceria, and Venusia. 34. Venusia.-As. Obv., dog's head, to left. Rev., fore-part of a wild boar, to left. Extremely rare, and well preserved; size 18. One, obv., shell; rev., three crescents and YE.; size 9. £10. Lots 35 to 67 were struck coins in silver and For in gold and silver the rust is prejudicial, and rocks, and the shaded portion that which has broken through and upheaved them. This species of rock is called igneous, unstratified, or amorphous, from two Greek words, signifying without form. It never occurs in the form of times a delicate blue, like that of a turquoise; regular layers, as the stratified rocks do, but always in irregular masses. All rocks, then, be-sometimes of a bronze brown, equal to that long to one of these two classes, but it is observable in ancient statues of bronze, and so principally by means of the aqueous rocks that highly prized; and sometimes of an exquisite the geologist traces the former history of the green, a little on the azure hue, which last is the most beautiful of all. It is also found of a fine purple, of olive, and of a cream colour or pale yellow, which last is exquisite. Neapolitan patina is of a light green, and when free from excrescence or blemish, is very beautiful. Sometimes the purple patina gleams through an upper coat of another colour, with as fine effect as In a few instances a a variegated silk or gem. rust of deeper green is found, and it is sometimes spotted with the red or bronze shade, which gives it quite the appearance of the East Indian stone called blood-stone. These rusts are all, when the We always find that if we go deep enough we at length come to some igneous rock, and we therefore conclude that the foundation,as it were, or interior of the earth, is a huge mass of amorphous rock. With this foundation geology has little to do, but confines itself chiefly to its shell or outside coating. In my next paper, I shall endeavour to show the successive revolutions which have rendered the earth habitable, and which have changed what must have be rocky wilderness, into the fruitful and pleasant abode which man now occupies. Until then I recommend my readers to study the subjoined list of some of the most ordinary rocks. AQUEOUS OR WATER-FORMED ROCKS. MUD OR SILT is the massing together of impalpable particles of rock, worn by water and deposited at the bottom of seas, and other large bodies of water. upon. MARBLE, LIMESTONE, AND CHALK are all of the same family; composed of carbonate of lime as a base; they are detected by a drop of sulphuric acid, which causes them effervesce. SAND is formed of the minute particles of waterworn rock; gravel is composed of the larger portion of these same rocks. SANDSTONE AND CONGLOMERATE are respectively consolidated sand and gravel. Conglomerate is also called pudding stone. QUARTZ is a massive crystalline rock. The small rounded white and yellow pebbles of gravel are pieces of quartz. IGNEOUS OR FIRE-FORMED ROCKS.-GRANITE is formed of crystals of quartz, felspar (a laminated glassy substance), and mica (a transparent glittering mineral). It is of various colours. BASALT is a hard dark rock, which always assumes a columnar structure. . bronze of New Latium, Campania, and Samnium. 40. Campania. Nola. Obv., laureated head of Apollo to right, and Phoenician legend. Rev., forepart of the human-faced bull to the right. An apparently unique obolus, fine, and splendidly patinated. Copper; size 4. £2 10s. The 50. Campania. Atella. Triens. Obv., head of Jupiter to right, and oooo. Rev., Oscan legend; fast quadriga to right, and oooo. Very scarce, fine, and valuable; copper; size 8. £3 10s. real product of time, as hard as the metal itself, and preserve it much better than any artificial varnish could have done, concealing at the same time not the most minute particle of the impression of the coin," The sizes of the coins refer to the scale of Mionnet, of which we give an engraving. 55. Campania; Marcina. Obolus. Obv., laureated head of Apollo to left. Rev., Oscan legend; dolphin and club. Very fine, and of great rarity. Copper; 4. £6. Lots 68 to 74 were silver denarii struck during the civil war. They realised high prices. Lots 75 to 266 consisted of Græco-Italian and Sicilian coins in gold, silver, and copper. From them we select the following: 82. Apulia. Venusia. Dextans. Obv., bust of Hercules to right, and VE. N. II. Rev., C.A.Q., the Dioscuri on horseback to the right. Fine, and extremely rare. Copper; size 11. £7 78. 91. Calabria. Tarentum. Drachm. Oby., Taras riding on a dolphin, to the right. Rev., ΦΙΛΙΑΡΧΟΣ, rider to the right, throwing his javelin. Very rare, and in splendid state. Silver; size 4. £5 2s. 6d. The obverse of this coin represents Taras, the son of Neptune, and the legendary founder of the city, which was called after the name of its founder Taras. 96. Lucania. Metapontum. Didrachm Obv., Hercules naked, with lion's skin head-dress, sacrificing at an altar, and leaning on his c'ub. Rev., META., an ear of wheat. Well preserved; an unpublished variety. Silver; size 6. £8. The ear of corn, sacred to Ceres, was early adopted by this people, in token of gratitude to that divinity for the fertility of their country. 98. The same. Didrachm. Obv. female head to left, with HOMONOIA. Rev., META., an ear of wheat. Very fine, and of the greatest rarity. Silver; size 5. £10 2s. 6d. 120. Bruttium. Croton. Didrachm. Obv., a tripod beThe exergue of a coin is that part which is tween a serpent and an ear of wheat. Rev., divided from the field by a line, upon which the KPOTONIATAN, an eagle to the left; in figures of the reverse stand. The field is the open * A travelling cap with a broad brim. laws a branch. A very fine coin of fine style workmanship. Silver; size 5. £6. 131. Bruttiùm. Rhegium. Tridrachm. Obv., head of a lion, full-faced. Rev., RECINON retrograde; a calf's head to left. A fine coin of great rarity. Silver; size 6. £7 2s. 6d. The obverse of this piece bears the usual Rhegian type, and the reverse the Samian type. 133. The same. Tetradrachm. Obv., full-faced head of a lion. Rev., PHRINON, laureated head of Apollo to the right. Silver; size 7. In splendid preservation, and of magnificent style. £9 98. 147. Sicilia. Agrigentum. Obr., two eagles holding in their claws a hare, ETPATON. Rev., APPATANTINON, a quadriga to the left, with horses in strong action; above, a vine branch. Silver; size 7. A very fine and unpublished variety, worthy of a great price. £30. 148. The same. Obv., an eagle to the left, AKPATANTO2. Rev. a crab. Very fine. Silver; size 6. £5 5s, "This city was built upon the river Acragas, so called probably from abounding in crabs, Xoay ov, from which circumstance the crab, being perhaps at an early period made sacred to the river deity, became the principal type of the money of this city, and was never discontinued, either as principal or secondary, among the types of the national coin. The ancient name of the city was the same as that of the river, Acragas, but became eventually Agrigentum, or rather Acragentum. Aeragentum' was originally built upon Mount Acragas, and the existing ruins near the modern city of Girgenti, attest its ancient extent and splendour. On coins of this city, of the fine period, the obverse is generally an eagle destroying a hare, a type which has been very variously explained." 164. Sicilia. Camarina. Obv., youthful head of Hercules with lion's scalp to left; ΚΑΜΑΡΙΝΑΙΩΝ, Rev., a helmeted charioteer leading his quadriga at full gallop to right, and crowned by Victory; in the exergue two hydria or amphora. Silver; size 7. Very fine and very rare. £10 15s. 165. The same. Obv., helmet to left on a round shield. Rev. KAMAPINA, palmetto with fruit, leaves, leg armour, etc. Silver; size 5. Fine and extremely rare. Another. Obv., bearded head to right, rev., helmet. Silver; size 14. £15. 167. Sicilia. Catanea. Obv., laureate head of Apollo, adv. between bow and lyre, between the artist's name AгоAAQN. Rev., KATANAION, a charioteer, crowned by Victory, guides a fast quadriga to right, near a pillar; cray-fish beneath. Silver; size 7. Very fine, and rare to excess. £25. 172. Sicilia. Eryx. Silver; size 7. Obv., EPYKINON. The Erycinian Venus seated to the left, on her extended right arm a bird with open wings; Cupid in front, standing. Rev. a charioteer, crowned by Victory, leads a quadriga at full gallop to the right. In beautiful preservation, and of the very highest rarity; it formerly belonged to Dumersan, Raoul-Rochette, then to Rollin, Dupré, and to the present proprietor; unknown in Torremuzza's time; none in the Thomas cabinet. £48. 173. Sicilia. Gela. Silver; size 7. Obv. TEAAE, human-headed bull to the left, immediately before its face bulrushes springing from the ground (river Gela); in exergue a grain of barley. Rev. a quadriga to the left, the horses in extreme action, wheat beneath, above, an eagle flying to the left. Fine, especially the obverse, and very scarce. £16. This curious type of a human-headed bull is most likely a personification of the river Gela, which flowed near the city of that name on the south coast of Sicily. 201. Sicilia. Naxus. Silver; size 7. Obv. head of Bacchus (the face has the genuine Bacchic expression), crowned with ivy. Rev., NAZION, full-faced faun resting on a wine-bag, with cantharus and thyrsus as on gems; ivy branch on his right side. Very fine and rare, of good Sicilian style of work. £13. 205. Sicilia. Segesta. Silver; size 7, Obv. a head of Segesta to right, with broad fillet and reticulum; wheat beneath. Rev., ZEREZTAION, young hunter to right, with conical cap or helmet on his shoulders, secured by a cord, which he holds in his left hand; two dogs at his feet. Extra rare, in magnificent preservation, and of good style of work. £58. 215. Sicilia. Syracusa. Gold; size 24. A taukard or drinking vessel. Obv., head of Apollo to left. Rev. EYPAKOZION, EMIGRATION. A FEW REMARKS ON VICTORIA. may was almost unnoticed and unimportant. At that time it received an inundation of population; every article was raised to fabulous prices, and a very inadequate supply of land was put into the market for sale by the Government at a time when the country was rapidly expanding its resources, means and population. The combined results of these incidents were the maintaining of a high price for agricultural produce-of course other sources poured into this colony their superabundant produce-land was extensively sold, and the result was a continual decrease in the price of cereals, &c., for several years. A glance at the imports of Victoria will show the extensive trade which has been carried on. For several years, therefore, prices were depressed below the average, but latterly the causes which conduced to this state of affairs has been removed, and the conse. quence necessarily followed that a more healthy and profitable state of things rose into existence. Another cause again assisted towards this result. The first attempts at farming savoured of extreme laziness and ignorance. The same piece of ground excellent results, then fair, muddling, and bad was sown with wheat year after year, at first with respectively. A different system led, as above, to better times. If my During late years the vine has been largely cultivated. Mr. Westgarth says:-"The interior parts of the colony seem most suitable for vines, where the warm sun of summer alternates with a trict is already a scene of yearly vintages, and in touch of sharp winter's frost. The Murray disconjunction with the district of the Murrumbidgee, has commenced the methodical plan of public auctions of the wine produce." memory serves me right, however, a gentleman writing to one of the colonial papers last year, regarding his plantation, stated that on some soils the vines were not over productive, and were liable to numerous "complaints," such as mildew, &c. Though the coast rivers of this colony are neither so deep nor so broad as those traversed in the interior by several of the larger of New South Wales, it is skirted and in part streams of south-eastern Australia. The Murray, Goulbourne, Ovens, and the Hume, in their extent and volume of water, in conjunction with with water, and leave it little liable to drought. those on the coast, sufficiently supply the colony Its remaining large rivers are the Yarra Ya ra, on which the town of Melbourne is built, the Glenelg, forming one of the boundaries of the province. The IN reply to various correspondents I will in circumference.' I The boundaries include an area of about 150,000,000 square acres. Gipp's Land is one of the finest tracts in the province, including more than 300,000 square acres adapted for perminent settlement. Its soil is richly alluvial, its temperature moderate, and adapted to European constitutions, while from its situation in the vicinity of the snowy mountains it is abundantly supplied with water. Another portion of the colony situated between Geelong and Portland Bay may be also noticed for its fertility and the advantages it offers to the occupier Mr. Malcolm says: "I consider that the district of the do not think there is richer land in any part of the Lake Colach for about 200 miles is very rich. world-it is as good land as ever plough was put The climate of Victoria is well suited to wheat into; there are thousands of acres adjoining Lake growing. To the remarkable dryness of its Colach, clear of timber, and the richest land I weather we may perhaps chiefly ascribe that ever walked or rode over, well supplied with white and flour-like quality of grain, and thinnesstreams and lakes, one of which is twenty miles of skin, that are the characteristics of the best wheat. In England, it may be remarked, the dry years are always the best for wheat, as the bran is then least in proportion to the flour, while the grain shows its quality by the only true test, its increased weight. It may however be thonght that the alternate hot and wet climate is detrimental as a whole to agriculture. Yet it is not The above will give some slight ideas regarding so, for the strong sun power, cloudless sky, and the agriculture of this important colony. If any the hot wind are features not usually at their full reader desires further information, I would and damaging development until the summer his recommend to his notice a prize essay on the advanced sufficiently to place the crops beyond Agriculture of Victoria," by W. Story, Esq.; danger. The fierce sun and the fiery breath he ha-lso Westgarth's "Colony of Victoria;" and inkindled in the interior of the country, expend tending emigrants should get some late numbers their powers in the most cases harmlessly on field of the Melbourne Argus, an excellent colonial of stubble; or if they come at an earlier upon the farmer, they but quicken his movements stage Lastly, I should state that many colonists do to meet an accelerated maturing of his crop. I may, perhaps, be remembered that Victoria took no less than fifteen medals and sixteen honourable mentions in the department of wheat alone at the Great Exhibition. Although the samples of Victorian produce are so good, it has been stated that agricultural pursuits have not always been remunerative. This can very well be ex; laine ! As a colony, Victoria, before the "golden era," Most of the English domestic animals thrive well in Victoria. The sheep especially is very prolific, and the wool annually exported forms a large item in the trade reports. Horses, pigs, poultry, &c., &c., are to be found in large numbers. paper. not wish emigration to this colony to continue. but an unbiassed mind would say, "Go and prosper." P.S.-If any reader receives the Argus and would not mind, he would confer a favour upon the writer by forwarding it, per the Editor, as I have not seen it for the last few months. I would gladly defray postage. (To be continued.) WHITWORTH SCHOLARSHIP EXAMINA the vertical trace one of 50 deg. Determine the TION PAPERS. FIRST STAGE, or Elementary EXAMINATION. Special Instructions for this Stage.-By well considering the question he is about to attempt the candidate will be able to get all his work, without any crowding or confusion, on the one sheet of drawing-paper given out to him, for he must understand that no second sheet will be allowed him. He is not to attempt more than eight questions in this paper, and, to obtain a class, at least two of these must be from the solid geometry. The questions in the plane geometry are of equal value. In the solid geometry the relative values are given by the members in brackets. The constructions may be left in pencil provided they are distinct and neat. They must be strictly geometrical, and not the result of calculation or trial. The absence of those lines which would be essential to a correct solution will show that the figure is worthless, however correct the result may appear. Lines parallel or perpendicular to others may be drawn mechanically without showing any constructiou. : Plane Geometry.—(1) Draw two circles touching one another and a straight line. Radii ·5in. and 75in. respectively. (2) Find a point P in a line A B (3in. long) produced so that AP: A B as 7 4. (3) Draw an equilateral triangle of 3in. side. From a point P in one side 5in. from the corner, draw a line which shall bisect this triangle. (4) Draw a triangle two of whose angles are 50 deg. and 65 deg., and the radius of the inscribed circle lin. (5) Draw a square of 2.5in. side, and divide into three equal parts by lines drawn from one corner. (6) Six radii meet in a point O and contain equal angles; OA = l·lin., OB 1.3in., OC 1.5in., OD = 1.5in., OE = 1·4in., OF 1.2in. Join the points ABC...F, and determine a triangle equal in area to the figure so formed. = Ex. I Ex. 5 Ex. 20 ・metal... INS.121 kiell inclination of the plane and the true angle between the traces (6).-(9) Taking the traces as in the last, in this plane place a line (length at pleasure) inclined at 35 deg., i.e., show the plane and elevation of the line (7).-(10) A pyramid having for its base a square 2.5in. side, the horizontal plane. and its axis 3.25in. long, rests with one face on Draw i's plan, and a sectional elevation on a vertical plane represented by a line bisecting the plan of the axis, and making an angle of 60 deg. with it (6).—(11) Draw the plan of an equilateral triangle of 3in. side, when so held that its corners are at 9in., 1.6in., 2.5in. respectively above the horizontal plane (5).-(12) Draw the plan of the square pyramid mentioned above when its base is inclined at 47 deg. and one edge of that base at 27 deg. (8). drawing-paper given cut to him, for he must understand that no second sheet will be allowed him. He is not to attempt more than eight questions in this paper, and, to obtain a class, at least three of these must be from the solid geometry. The relative values of the questions are given by the numbers in brackets attached. The constructions may be left in pencil, provided they are distinct and neat. They must be strictly geometrical, and not the result of calculation or trial. The absence of those lines which would be essential to a correct solution will show that the figure is worthless, however correct the result may appear. Lines parallel or perpendicular to others may be drawn mechanically, without showing any construction. Plane Geometry.-(21)Construct a regular pentagon whose diagonal shall be 3in. (9).-N.B. -The "" diagonal is from A to C in the figure ABCDE. (22) Divide Ex. 6 Ex. Ex. 8 ELEMENTARY Ex. 4 EXAMINATION 112 INS. SCALE OF 3 INS. I FOOT 12 FT. Solid Geometry.—(7) The plan of a line is SECOND STAGE, OR ADVANCED EXAMINATION. 2in. long and its elevation is 3in. jectors of its extremities are measured along ay. What is its true length and inclination? (6).-(8) The horizontal trace of a plan makes a angle of 30 deg. with ry, The proSpecial Instructions for this Stage (see general lin. apart, instructions on the first page).-By well considering the question he is about to attempt, the candidate will be able to get all his work, without any crowding or confusion, on the one sheet of R--10 Ex.27 Ex. 9 " Ex. 22 a square of 3in. side into three equal areas by line s drawn parallel to a diagonal (8).-(23) Draw a triangle whose sides are 2in., 2.5in., and 3in., and an equilateral triangle equal to it in area (10) -(24) Draw an isosceles triangle of 3.5in. area, the vertical angle being 35 deg. (10).-(25) The semi-conjugate diameters of an ellipse are 2.5in. and 1-3in. in length, and contain an angle of 63 deg. Draw the curve and determine its axes (10).—(26) On a certain drawing 1250 yards of real magnitude are represented by 15.5in. Furnish a scale for drawing, and also a comparative" scale of French metres. 1 metre = 1-0936 yard (10).—N.B. -The English scale may be 500 yards in length. Solid Geometry.-(27) A point P is 1-3in. above the horizontal plane, lin. in front of the vertical another Q is 75in. below the h.p. and 2.25in. behind the v.p. The distance between the projectors measured along xy is 2in. Determine the true length and inclination of the line P Q and also its traces (10). -(28) The horizontal trace of a plane makes an angle of 30 deg. with ry, the vertical trace one of 60 deg. Determine its inclination and the true angle between its traces [i.e., when the coordinate planes are in their proper position] (10)-(29) Determine the edge of a regular tetrahedron inscribed in a sphere of 3in. diameter. (15).-(30) A right prism, the section of which is an equilateral triangle of 2in. side, is 3in. long. Draw the plan of the prism when one of its faces is inclined at 42 deg, and a long edge of that face at 20 deg. (15).—(31) Determine the traces of three planes which are mutually at right angles, two of them being inclined at 35 deg. and 70 deg. respectively (15).—(32) Draw a circle of 1.25in. radius. This is the plan of a right cone 3.5in. high standing on the horizontal plane. Show the true form of the section of this cone, by a plane whose horizontal trace is 2in. distant from the centre of the plan, and whose inclination is 40 deg. (15). SUBJECT I.-PRACTICAL PLANE AND GEOMETRY. SOLID others may be drawn mechanically without the elevation of the whole pulley. Scale, 3in. to showing any construction. EXAMINER, PROFESSOR F. A. BRADLEY, (Second Paper.) General Instructions.-You are only permitted to answer questions from the elementary paper or from the advanced paper, but not from both. If the rules are not attended to the paper will be cancelled. In all cases the number of the question must be placed before the answer on the worked paper. Three hours are allowed for this examination. Plane Geometry.-(80) Find by construction 2 a , a being 2" in length, (6).--(81) Divide a line 3.5" long into two segments so that the 1 630000 showing furlongs by the diagonal method the foot (20).-(5) Manhole lid and seating. SECOND STAGE, OR ADVANCED EXAMINATION. FIRST STAGE, OR ELEMENTARY EXAMINATION. Special Instructions for this Stage.-By well considering the question he is about to attempt the candidate will be able to get all his work, without any crowding or confusion, on the one sheet of drawing-paper given out to him, for he (20) Air pump and condenser, with injection must understand that no second sheet will be valves, air-pump bucket, and foot and delivery allowed him. He is not to attempt more than valves, in section. To be drawn to a scale of one eight questions in this paper, and, to obtain a inch to the foot (90).—(21) Slipper guide for class, at least two of these must be from the solid horizontal engine. Partly in section and partly geometry. The questions in the plane geometry in elevation, and in plan. Scale, 3in. to the foot are of equal value; in the solid geometry the Solid Geometry.-(86) One edge of a cube is (80)-(22) Bracket pedestal. Draw also, if you relative values are given by the numbers in 2.5in, long, and inclined at 35 deg. A face per- can, a plan. Scale, 3in. to the foot (30).—(23) brackets. The constructions may be left in pendicular to this edge has one of its diagonals Fast and loose pulley. In section. Draw also, pencil, provided they are distinct and neat. They inclined at 25 deg. Draw the plan of the solid, if you can, the same view in elevation. Scale, must be strictly geometrical, and not the result and an elevation on a ground line assumed at 3in. to the foot (30).—(24) Steam piston. Longiof calculation or trial. The absence of those lines which would be essential to a correct solu- pleasure (12).—(87) An oblique pyramid stands tudinal and cross sections, and end view. Scale, tion will show that the figure is worthless, how- on its base, which is a regular hexagon ABC...F 3in. to the foot (25).-(25) Wrought iron crank of 1.5in. side. V is a vertex. The face V A B shaft. Side elevation. Draw, if you can, an end ever correct the result may appear. Lines parallel is inclined at 75 deg. to the base, V BC at 65 view also. Scale, lin. to the foot (30).-(26) or perpendicular to others may be drawn mechani- deg., V CD at 60 deg. Draw the plan of the Stuffing-box and gland. Complete the section cally, without showing any construction. solid, and state its height; also show the incli- and plan. Scale, 3in. to the foot (30).-(27) Plane Geometry.-(60) Draw a scale for a nation of the face V D E (12).—(88) Draw the Crosshead and ends of forked connecting-rod. drawing where 7.5ft. of real magnitude are re-isometrical projection of a block of wood 3-5in. Scale, 3in. to the foot (25). presented by lin. N.B.-The scale must be long loug, 3in. broad, lin. thick, with a circular hole enough to measure 50ft. from.-(61) Divide a of 2.5in. diameter bored through its centre (13). line AB 3.5" long in a point P, so that the -(89) Draw a circle of lin. radius, and take a rectangle contained by AB and AP may be equal point 2.5in. from its centre. The circle is the to the square upon BP. (62) Draw a triangle plan of a sphere resting on the horizontal plane ; whose sides shall be as 2: 35: 4, and whose the point is the plan of a luminous point fin. circumscribing circle has a radius of 1.5. (63) above that plane. Draw a pentagon whose area shall be 5.5 square inches. (64) A circle of 1-25in. radius has its centre 1'5in. distant from a straight line. Draw a circle of 2.25" radius which shall touch both, but contain the given circle. (65) Draw an isosceles triangle whose base is 2" and its vertical angle 40 deg., and another twice its area. Solid Geometry.-(66) Draw the plan and elevation of a point A which is situated above the horizontal plane, 2" behind the vertical plane, and is 3" distant from ry (6).-(67) A regular tetrahedron (edge 3) stands with one face on the horizontal plane. Draw its plan, and an elevation on a ground line which makes an angle of 15 deg. with one side of the plan. Show also the sectional elevation on a vertical plane which bisects one slant edge, and cuts off one quarter of another (8).-(68) Draw the plan and elevation of a line (length at pleasure) which is inclined at 30 deg. to the horizontal, at 40 deg. to the vertical plane. (69) An hexagonal pyramid (side of base 1'5in., axis 4in.) has one edge of its base horizontal and the plane of that base inclined at 60 deg. Draw its plan, and show the real form of the section made by a horizontal plane bisecting the axis when the solid is so inclined (8).(70) An isosceles triangle whose vertical angle is 30 deg. and base 2in. revolves upon that base so that the plans of its sides are at right angles. Determine the inclination of the plane of the triangle, and of the sides (7).-(71) Draw the plan of an octahedron of 3in. edge, when two of its diagonals are inclined at 26 deg. and 36 deg. (8). SECOND STAGE, OR ADVANCED EXAMINATION. Special Instructions for this Stage (see general instructions on the first page).-By well considering the question he is about to attempt the candidate will be able to get all his work, without any crowding or confusion, on the one sheet of drawing-paper given out to him, for he must Show the shadow of the sphere cast on the horizontal plane by rays of SUBJECT II.-MACHINE CONSTRUCTION DRAWING. AND HOW TO COLLECT AND STUDY INSECTS. ONE It NE can scarcely walk a mile in the country without obtaining some object to grace his cabinet, or observing some fact in natural history to add to his storehouse of mental treasures. should be borne in mind by the student collector that, notwithstanding he may propose to confined his studies to one order of insects, he should also contract a habit of observing and collecting those of other orders, as well as such small and portable vertebrates and other invertebrates as his oppor-tunities may enable him to capture and preserve. Alcoholic specimens of mammals, birds, fishes, reptiles, mollusks, crustacea, and facts concerning them, are marketable commodities in the exchanges of Science. Especially should this plan be carried out by the collector who may be established for a EXAMINER, W. CAWTHORNE UNWIN, B. Sc. term of months or years in a region remote from General Instructions.-You are only permitted libraries and museums. Such study and investito answer questions from the elementary paper gation in this field as his time permits, will of or from the advanced paper, but not from both. itself materially enlighten his mind upon the If the rules are not attended to the paper will be secrets of Nature; and although destitute of cancelled. The candidate is expected to prove his books-those records of repeated failures and few knowledge of machinery, as well as his power of successful attempts to unmask Nature's protean drawing neatly to scale. He is therefore to supply face-he may learn the structure, habits, and details omitted in the sketches, to fill in parts comparative inteligence of the creatures around left incomplete, and to indicate by diagonal him. A subsequent opportunity may occur for shading parts cut by planes of section. Where him to ascertain, if so disposed, the different tech66 'Mouse, No. 7," more than one view of the same subject is drawn nical names imposed upon no credit will be given unless the different views Bird and Nest, XII," or "Bug, No. 427," and are properly projected one from the other. A accepted by the scientific world. little consideration will enable the candidate to arrange all his work on the sheet of paper given out to him; for no second sheet will be allowed. The value attached to each question is shown in brackets after the question, but a full and correct answer to an easy question will secure a larger number of marks than an imperfect answer to a difficult one. If you have not proper scales with you, you may use the scales engraved on the drawing. The dimensions inserted to guide you need not be inserted in your drawing. Four hours are allowed. FIRST STAGE, OR ELEMENTARY EXAMINATION. Should he care only to acquaint himself with the nomenclature of some limited group or order, and wish to increase his cabinet in that specialty, he will find that he has the powers of a capitalist to invest his miscellaneous collection of specimens and facts in such manner as he may prefer. Thanks to the diversity of tastes implanted in us, there is always some eager specialist-individual or backed by an association-standing ready to give value for, and "work up" this or that portion of such material. The practice of noting (with ink if possible) in observations as he may make or discover, adds ima small blank book, or on cards, such facts and understand that no second sheet will be allowed him. He is not to attempt more than eight You are only permitted to attempt five ques-mensely to the value of any collection, and cannot questions in this paper, and, to obtain a class, tions. You may select those from any part of bo too strongly recommended to the collector. at least three of these must be from the solid the paper. Read over the general instructions The date of capture of a specimen, of the transgeometry. The relative values of the questions before commencing. formation from the egg, larva, or pupa, of the apare given by the numbers in brackets attached. (1) Wrought iron crane hook. Scale, three pearance or disappearance from its usual haunts, The constructions may be left in pencil, provided times that of sketch, (10).—(2) Wrought iron and such other items of interest that arise in conthey are distinct and neat. They must be strictly crosshead. Scale, 3in. to the foot (15).-(3)nection with the specimen, are of importance to geometrical, and not the result of calculation or Cast iron water tank. Only a small part of one the student, and should be therein set down. trial. The absence of those lines which would corner is to be shown, as in the sketch. Draw small tag or ticket of paper attached to the dry be essential to a correct solution will show that also, if you can, a section through a b of the specimen, or of parchment, leather, or soft metal the figure is worthless, however correct the result same part. Scale, 3in. to the foot (15).-(4) to the alcoholic, and bearing a number correspondmay appear. Lines parallel or perpendicular to Belt pulley. Section and elevation. Complete ing to that in the note-book, renders the informa. A |