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be very considerable-though to some extent dependent on the kind of iron used in the boiler as well as in the temperature-and often explosions thus ensue from the "breaking of the back" of the boiler. To keep the diameter of these boilers within bounds, the French have largely employed the compound form known as the Elephant boiler (Fig. 14). A boiler slightly differing from this in detail, but on the same principle, bears the name of the Retort boiler, Fig. 15. The next improvement aimed at economy, and gave us the Cornish boiler, Fig. 16. To obviate the weakness of the larger flued boilers of this class, Mr. Fairbairn introduced the Double-flued boiler, Fig. 17, about twenty-five years ago.

HIGH PRESSURE BOILERS.

These boilers are very safe, and in somewhat extensive use, though by no means to the extent they merit. Considerable numbers of Butterley boilers have been constructed (see Fig. 18), but although they are economical, they are very weak against pressure, and therefore proportionately dangerous. Many minor varieties of boilers might be mentioned. One class of boiler-from its dreadfully destructive nature-claims attention, namely the class used in ironworks. These boilers, surrounded by brickwork, and exposed to the fierce flames from the puddling furnaces, would be sufficiently destructive in any ordinary situation; but, placed as they are, in the very midst of a number of men, amongst whom, when

they explode, they scatter a death-dealing shower of bricks, iron, and water, with the frequent addition of some of the hot iron from the furnaces, the carnage produced is often frightful.

The Multi-flued boiler (see Figs. 19 and 20). demands but little notice, as it has not been found satisfactory in practice, since its economy in fuel is more than counterbalanced by its being troublesome to clean. The Multi-tubular boiler is still more economical in fuel, but also still more difficult of access for cleaning. It is also liable to leak at the bottom, and from those two causes is wanting in durability. It is particularly unsuited to foul feed-water. Amongst the improvements made in boilers of late years Adamson's

th-dealing

the frequ

om the f

ghtful.

Figs. 19

it has not

ince its e nced by its

-tubular b

t also still

It is also b

hose two ca

particularly

gst the imp

ears Adam

FIG. 1.

Blankley's Simple Sliding Selenite Stage, FIG. 2.

Blankley's Compound Selenite Stage, giving 28 changes of tint and colour.
ACCESSORIES TO THE MICROSCOPE. Described on page 462.

boilers are also least likely to adopt so beautiful
a contrivance as the injector. In fact, the writer
himself some little time back took out an old
feed pump and put an injector in its place, which
gave the utmost satisfaction. Some little time
after the boiler passed from under his control,
when the pump was reinstated, merely on the
plea that the injector was "too scientific."

inch, the very great superiority of such a material to iron, only capable of bearing 20 to 22 tons, needs no lengthened comments. The use of steel for boilers has been much restricted by the general impression that the steel must be drilled and not punched. That drilling is, per se, better than punching we feel convinced, but is it not just as superior for iron as steel, if the latter be afterwards annealed?

flanged joints in internal flues, and Galloway's
conical tubes occupy most important places. The
strength afforded by the flange joints is very
great, and when the frequent collapse of long
flues is taken into consideration, is very important.
Galloway's tubes, Fig. 21, not only materially
strengthen the flues, but they also add a most
efficient heating surface, as the flame and gases
strike almost at right angles to the metal, while
the water rises at a slight angle from it, the best
possible conditions for evaporation-and thus they
are valuable economisers of fuel. They also
cause a very brisk circulation, which further
tends to economy, and to the preservation of the
boiler by equalizing the temperature of the water
throughout, and so preventing unequal strains.
It is probable that if inner tubes were added, as
shown in Fig. 22, that the efficiency would be
still greater, as such inner tubes would separate
the water into two currents, upwards and down-
wards. All the boilers we have hitherto noticed,
differing as they do largely, inter se, have one
peculiarity in common, namely, that they each
contain a large volume of water and steam. In
case of an explosion there is, therefore, a corre-
spondingly large supply of destructive material.
Further, they are each to some extent deficient in
economy of fuel, as they allow the heated gases
to slide to too great an extent along their heating
surfaces, not breaking up the current sufficiently;
and they are also, as a rule, wanting in circula-
tion. These last objections do not apply much
to Galloway's boiler, the first does. Many at-
tempts have been made to so construct boilers as
to be free from these objections, and also to carry
high pressures. An early labourer in this field
was Dr. Ernst Alban, of Plau, who produced a
very able and exhaustive treatise on boilers about
a quarter of a century ago. He discusses pres-
sures up to 1,000lb. per inch. He was the origi-
nator of some very ingenious water-tube boilers. As
these boilers have, however, become obsolete, they
hardly fall within the scope of the present article.
James and others proposed tubular boilers,
having an extra inner tube to promote circulation.
These inner tubes by no means answered the pur-
pose for which they were intended, as the upward
and downward currents met each other at the
tops of the two tubes-inner and outer-and the
circulation was far from being satisfactory. Mr.
Field combatted this difficulty by splaying the
top of the inner tube, which thus become trumpet-
shaped. That the "Field" tube answered its
purpose may be gathered from the favour it enjoys
and the large number-upwards of 60,000-in
It has been found extremely applicable to
fire engines, as it is a very rapid generator, so
much so, that steam of 100lb. per inch has been
raised from water at about 45° Fahr. in 74 minutes,
in a boiler fitted with these tubes. These boilers
are extremely suitable where quickness, high
pressure and economy of fuel are required; and
where constant and competent supervision is given
to the firing and "feeding." They are not likely,
however, to be generally adopted for factory and
other uses where more liability and neglect exists.
We have now to notice a boiler which is, per-
haps, in most respects the best yet introduced.
The one we allude to is Howard's Safety Boiler.
This boiler possesses the following requisites of a
good steam generator :-It affords ample heating
surface of the very best kind for efficiency, as the
flames and currents of gas are thoroughly broken
up by the alternations of the vertical tubes. It
offers a maximum amount of safety at high pres-
sures; in fact, it is doubtful whether more than
one tube would go at a time, even if an explosion
did occur, which is very unlikely, as the tubes
being small are of enormous strength, and are
further, by reason of their shape, subject to
simple tensile strains only, and therefore no very
extensive damage would be likely to accrue. It also
acts as a very efficient superheater, thus giving the It is very probable that far too little atten-
two great advantages of very high and perfectly dry tion has been bestowed on the electrical in-
steam. Inasmuch as corrosion and scaling are un- fluences brought to bear in corroding the iron of
doubtedly the two most serious evils which have boilers, where the plates and rivets differ in
at all times attended boilers, so must importance amount of carbonization, &c. Bessemer steel
attach to the fact that in Howard's boiler so good offers a very suitable material for boilers of all
a circulation is obtained as to do away with the kinds, and of late very considerable advance has
accumulation of scale.
In these experiments eight plates of steel had
A further great advan- been made in its application. As a proof of this each four holes of 0.66in. diameter punched in
tage lies in its non-liability to injurious strains, it may be mentioned that up to March, 1868-them. Each plate was then cut in two, and one
as its construction admits of its yielding in all since which we have no return-three firms in
directions to the expansion and contraction con- Lancashire had turned out no less than 277 steel
sequent on changes of temperature. This boiler boilers, and 152 composition boilers, partially of
is also remarkably easy to repair. The only steel.
drawback to it lies in the rapidity with which the That these numbers are far under the mark
water will rise or fall in it. This difficulty is now may be inferred from the fact that the
nowadays met, to a great extent, by Giffard's in-demand was then rapidly increasing. As steel
jector; but it must be borne in mind that the of great ductility can be got capable of bearing
very class of users most likely to neglect their an ultimate strain of 33 to 35 tons per square Naval Architects, 1868.

[graphic]

use.

With regard to punching steel plates, we have before us the results of a very careful set of experiments carried out by the Bolton Iron and Steel Company, and, from their important bearing on the question of increased safety with high pressure boilers, we give the tabulated results. Six pieces 23in. long by 7in. broad and 5-16in. thick, were cut from the one steel plate. Three of these were prepared by punching, and three by drilling, with gin. holes, 1in. from centre to centre, suited for single and double riveting. In a strapping machine these were then cut to the forms shown in Figs. 1, 2, and 3.

As regards the future of steam boilers, we may
expect that high pressures will continue to be-
come more general as their economy is more
widely appreciated. At the same time, let us
hope that the increased dangers resulting may be
guarded against by an efficient system of inspec-
tion and improved workmanship and materials in
the boilers, with the more extended use of double
lock-up safety valves and alarums, fusible plugs,
and trustworthy water and steam gauges in du-
plicate. At the present time it is dreadful to
contemplate the numbers of boilers working
literally at random. The writer went a few days
back to a place where they had had an explosion
of a boiler, which, though fortunately unattended
by loss of life, had been fearfully destructive.
Yet, notwithstanding this severe lesson, they had
actually put down an externally-fired cylindrical
boiler-a most unmanageable and mischievous
form-without water or steam gauge, or even a
fusible plug or alarum: its sole safeguards
being a float with a stuffing-box, and a most
inefficient safety-valve weighted to sixty pounds.
At the time of our visit the steam was blowing
off furiously, so that the pressure must have
been much above 60lb., very likely nearer 100lb. (1 D.
per inch. The danger was by no
diminished by the fact that the boiler was made
with lap joints, and, of course, single riveted.

means

If cylindrical boilers are to be used at high pressures, the bodies and flues ought to have the longitudinal joints welded, and each length rolled to a truly circular shape, The transverse joints ought all to be double butt joints, and the plates thick edged, on Alton's plan. As regards rolling a tube, why should not complete bodies and flues be rolled at once? It is only a question of size of machinery and careful design. The demand for such boilers could not fail to be large.

weight. The results are given in Table I.:They were tested in a lever machine by dead.

Num-
Thick Area.
ber of
ness.
Test.

TABLE I.*

Breaking Weight Weight weight per sq. in. per sq. in. on Lever. of section of section drilling. punching.

Tons cwts

5

0.5437

19

35.32

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1 P.

26.690

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be seen that there is a difference of 11.742 tons in favour of the annealed plates, equal to 55-66 per cent. It is further well worthy of notice that the annealed plates are very much more reliable, as they show a difference of only 5-416 tons between the two extremes, while the unannealed vary as much as 9-372 tons.

TABLE II.*

more efficient legislation. Let us hope also that
the barbarous system of buying boilers at per ton
may give way to an intelligent mode of valuation.
When this is done, and the great value of pure
feed-water recognized, we may expect an ex-
plosion to be a rarity.

A further improvement required is the entire
remodelling of Crowner's quest-law," by which
a coroner, who knows little or nothing of boilers,
is assisted (?) by a jury, who usually are chosen
Breaking strain as thongh it were desirable to get those who know
"nothing of anything."

per square in.

Tons. 19.89

26.369

24.460

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Anneal- Unan-
ed. nealed.

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23 781

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We want a competent tribunal to inquire into
all explosions, accidents on railways, in mines,
At present
&c., whether actually fatal or not.
we witness this absurdity, that a minor accident
may occur by which one life is sacrificed, and two
coroners set to work; on the other hand, an acci-
dent which maims hundreds for life will not
move one coroner, unless some case of death
should result. These are the abuses of a bygone
age which have dragged on to the present.

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organized food, either animal or vegetable. Cer animals require animal food, others can live with out that; but some can maintain life without a least food derived from the vegetable kingdom Following down the scale of organization, we fol that vegetable life and growth require the prese of matter arranged at least into binary compounds. Vegetable tissues are made up of carbon, hydroge oxygen, and nitrogen, but, so far as known, tow elements are always obtained by plants from matt organized or arranged in compounds such as cr bonic acid, ammonia, &c.*. These compounds may be, and at present are, in part derived from animal kingdom, though not necessarily so, for the result from the breaking down of vegetable matte and may be naturally produced by union of the elements.

Although the animal kingdom cannot be min tained without vegetable food, the vegetable ki dom may be without animal food; and althos vegetable life and growth cannot be maintai without matter arranged at least into binary pounds, these compounds which serve as food plant-life can be formed and maintained with the aid of animal or vegetable matter. The a kingdom is then essentially primarily supplied food from the vegetable kingdom, and this, in from binary and higher compounds. The com compounds, chemistry teaches us, are formed union of simpler ones, and the simplest by union of elementary atoms.

These seem to be universal laws, to which are no known exceptions.

NOTE. The annealed portions are shown in antique | Blankley brought before the notice of the Fellows a proper form their constituent elements. If

type.

It is advisable in making steel boilers to use double butt joints and double riveting, as otherwise the rivets will sheer with far less than the breaking strain of the plate; unless, indeed, the rivets used be so large as to gain strength to the detriment of the plate. The proportions given by Mr. Henry Sharpe, of Bolton, are for 5-16in. plates, diameter of rivets, 9-16in., pitch, 1gin., double riveting; material of rivets, mild steel. With these proportions two tests gave the following excellent results, with plates taken at random from a large quantity of steel boiler plates which were being rolled to order by the Bolton Company (a), drilled plate 42-9 tons, and (b) punched ditto, 39-11 tons per square inch of net sectional area. Mr. Sharp further experimented as follows:

of the Royal Microscopical Society, two forms of
selenite stages, which possess two great ad-
vantages: first, simplicity of construction; and
secondly, the ease with which they can be worked.
It may not be known to all our readers that
different thicknesses of selenite give different
colours, and that the structure of some objects
can be seen much better with one colour than
with another. It will therefore at once be seen
how desirable it is to view each object under every
tint, so that the best effect may be secured.

Fig. 1 consists of a small brass stage, 34in.
long and 14in. wide, in the centre of which is an
the under part of the stage is a dovetail groove,
aperture through which the object is viewed. On
into which is fitted a brass slide containing three
or four selenites, which work as freely as the in-
A small spring stops the
vestigator may desire.
slide when the selenite is immediately under the
aperture.

Food is essential to the growth of all organi Growth being an increase of the elements of wi a body is composed, in certain definite proporti and having the arrangement proper to the grow body, it is in fact a continuation of the process organization, and the food required for growth ma at least be required for the first organization creation; for the food of all organisms contains crystal be placed on the solution from which it was formed, it will, under proper conditions, grow. One condition to its growth is the supply of its proper food, which consists of the same elements, having the same arrangement as required for its first fa mation. The seed of a plant exposed to moisture absorbs water, and sap or food is formed from the material stored up in the seed which had been separated from the watery portion of the sap contained in the parent plant; when its supply of matter, which by the addition of water serves as food, is exhausted, more is supplied from the surrounding air and soil. Like the crystal, so long as its proper food is not furnished, the germ of the seed remains stationary; and when again, under through the action of the organizing forces proper conditions, supplied with constituent matte nature, it grows. Animal tissues grow by mean supply of blood, the composition of which d in different kinds of animals, but is essentially same solution as the blood of the parent from the germs or eggs of each were formed. In these cases it is not necessary that the solution

a

but that must be present.

A punch of 11-16in. was used; first, in the ordinary way, with a bed in. bare, producing the hole shown in Fig. 4; then a bed, fin. in diameter was used, giving the result shown in Fig. 5. Fig. 2 represents the compound stage, which The plates were dressed to the form shown in consists of a brass stage of similar dimensions to the food should contain only the constituent mat the one just described; and, in addition to the brass slide, has a revolving diaphragm with three selenites, each made to rotate, and a clear aperture, so that the object may be viewed with a single film if desired. In this stage each selenite is much larger than those in the small one, and is marked in quarters, so that the colours obtained may be registered and turned to at any time.

Fig. 6. When tested, which was done without an nealing, the taper-holed plates gave an average of 32-527 tons per square inch of net sectional area; the plates with straight holes, 26-004 tons. These taper holes must offer advantages to riveting up. It is certain that the desire for economy will lead to the more extensive adoption of high pressures, heated feed-water, and the super-heating of steam. As regards the heating of feed-water, we may notice "Green's Economizer" as a very efficient apparatus. Its chief peculiarity, as is well known, consists in the scrapers-which are very slowly moved up and down by simple gearing

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It is, moreover, important to notice that this stituent matter must be to a certain extent p viously organized. This may, perhaps, be bet understood if we notice first the formation of crystal, which may be considered as illustrating formation of all organic germs. Crystals form solutions having the organization proper in crystal; the solution must not only contain a the crystalline compound. For instance, a se elements of which the crystal is composed, but must be arranged in molecules, correspondin may contain soda, chlorhydric and sulphuric and crystals of chloride of sodium will not because the constituent elements, although are not combined or arranged with the prop nite relation to each other. Crystals of su soda will form from such solution, un per conditions, because its elements are bined.

The positive axis of each selenite in the dia-to clear off the soot from the pipes through phragm is marked coincident with those in the which the feed is passed. By this clearance the slide. By working each film as thus described, pipes are kept efficient in absorbing heat. Very considerable saving of fuel has been effected by twenty-eight tints and colours will be obtained, the use of this apparatus. Waters's heater is ex-be observed that the whole of the changes are and can be recorded for further reference. It will ceedingly suitable for non-condensing engines. obtained without moving the stage or taking the formed from the sap, which is the pla It possesses the advantage of thoroughly heating object out of the field or focus, thus saving much the water to the boiling point, and also of causing time and trouble. They are made by Mr. Swift, the deposit of its earthy matters as mud in the heater. With the increase of pressure, the fre- 128, City-road, London, who is preparing a comquency and destructiveness of boiler explosions plete list of changes that can be effected by them.

will increase unless efficient means be taken to combat the dangers spoken of.

ORGANIC LIFE.

BY H. B. BAKER, M.D., of Wenona, Mich., U.S.

BIOLOGICAL EVIDENCE.

Any one who will read the reports of any of the very excellent boiler associations will be convinced that, if boilers were all well made to begin with, as regards workmanship, design, and THE ORDER OF CREATION OF LIVING BEINGS, FROM material, well mounted with efficient duplicate safety-valves (locked), water-gauges, alarums, steam-gauges, and fusible-plugs, and finally, properly inspected, explosions would be few and far between. It is to be hoped that the Bill on this subject, introduced by the hon. member for Dudley, may either become law or lead to even

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The pollen and seeds as well as buds of pe selected from the surrounidng earth and ar matter organized in the manner peculiar to plant; it is, in fact, the germ of the plant in soluta and seeds may in a manner be said to crystal from it. The spermatic fluid and eggs of anima are formed and perfected in an analogous man by compound molecules, separated or secreted f the highly organized animal fluids. The formati of the fluids from which these crystals, seeds,

eggs are formed, requires the presence of the fo proper to each, and it must consist of their const tuent matter properly arranged.

From what is known concerning the laws which growth, the essential nature and constitution of food, the formation of the germs of organisms and the formation of chemical compounds, justified in concluding that animal life is always

wo seem

BEGINNING with takes food, which is then
still further organized into the human tissues, and
thus in early life he grows; and throughout life
can only, through continued use of food, maintain
his existence. It is also known that he is only able
to assimilate matter that has been, to some extent,
previously organized; and this is true not only of
*It seems proper to state that this article was written
man, but of all animals. Even infusorial animal- before the writer had seen or heard of Professor Hus
cules require for their existence the presence of ley's lecture on "The Physical Basis of Life."

parent fre

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119 Article srd of Pr

its of Life

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necessarily preceded by vegetable life; that this is always necessarily preceded by a certain amount of arrangement of elements into binary and more complex compounds; that the complex compounds are aniversally formed from simpler ones, and the simplest by union of the elementary atoms. We can thus trace back the order of creation, or evolution of living beings, to the chemical elements.

THE BEGINNING OF LIFE. ITS LOWEST FORM, AND THE SIMPLEST ORGANISMS.

parts, and again show that the lowest living things are organisms.

tain extent, result from the forces acting upon it. As the atoms of an elementary body are alike, and, subjected to the same force, vibrate alike, and the This higher view is furnished us through a knowatoms of different elements are unlike, and vibrate ledge of chemistry, which teaches that there is differently, few or many changes will be produced a mutual dependence of parts which extends to the by a given force, according as it acts upon a body molecules, and even to the ultimate atoms of all deconsisting of one or many different elements. Afinitely combined matter. A definitely chemical given force should therefore produce the least num compound consists of definite proportions of matter ber and variety of changes by combination or re- definitely arranged. For instance, albumen is comarrangement, and by mutual reactions of consti- posed of carbon, hydrogen, oxygen, and nitrogen, tuent matter and force, will be least where atoms in certain proportions, and arranged in a certain of only one element are present. manner: if either the proportion or the arrangement be destroyed, the matter no longer constitutes albumen. The several elements of which it is composed may be considered as organs performing essential functions, their mutual dependence being absolute; for, if one be removed, the compound is destroyed. Probably the presence of each atom of each element is essential to the existence of the compound, so that a molecule of albumen may be considered an organism, although not in accordance with the idea heretofore entertained. The same may be said of a molecule of water or of any other such group of atoms definitely arranged. Albumen was selected as an example, because the lowest living things revealed by the microscope cannot, by the aid of the highest magnifying power, be distinguished from mere minute particles of albumen.

Motions result from force, and the greatest variety of motion will be produced by forces acting upon the greatest number and variety of elements. Motion of the simplest character results from the action of force upon homogeneous matter. Reproduction consists, essentially, in the generation of new bodies, and communicating to them the properties characterizing the parent, as regards both matter and its arrangement. The reproductive process should be simplest where the body to be reproduced is simplest, and we have seen that this must be the case when it consists of the least organizable quantity of one kind of matter, viz., of two atoms of one chemical element.

In studying the creation of living organisms, if we start with any of the higher animals, and trace back the life of an individual, we find it to begin in an organized form of matter, an egg. But the egg is a complex substance, and, although some of the conditions to its formation and development into a living being are well understood, studied by itself it is difficult to understand the creation, beginning, or source, of its vital force; and, if we understand from whence the force is derived, it is still difficult to see what gives direction. If we direct our attention to the vegetable seed, we meet with the same difficulties. In order that we may understand the creation of the higher organisms, it may be well to search out the lowest, and begin the study of life in its simplest form; and, that we may be able to recognize the object of our search, we should have a reasonably perfect definition of the word life, and an idea of the characteristics of living beings. A complete and perfect definition is difficult, and is not assumed to be here given; but it will be sufficient for our present purpose to say that, from the word life, we receive an impression of certain phenomena attendant upon changes which occur in organized bodies as results of their experiences of force. This definition is perhaps incomplete, but, in fact, any attempt at a perfect definition must necessarily be unsatisfactory so long as only the higher forms of life are considered. We cannot properly define a thing until the whole of it be some what understood. However, if we bear in mind our imperfect definition, and keep in sight the higher kinds of life which we do understand, we can search for the lowest, which we may not, and when the whole has been considered, a definition may be more satisfactory. Let us, then analyze the characteristics of the higher living beings from which we have received our first ideas of life, and learn their essential nature. By reducing these characteristics to their lowest terms, we ought to deduce an ideal lowest form of life.

The prominent phenomena which characterize living beings are-1. Organization; 2. Definite Chemical Composition; 3. Definite Form; 4. Growth; 5. Continual Change; 6. Motion; 7. Reproductive Power.

Our idea of life being mainly formed from our knowledge of these characteristics, the ideal lowest form should have them in the simplest degree. Commencing the search by considering them singly, we notice first that living bodies are organized.

If we now sum up these several least require ments, we find that, from this analysis of the characteristics of living organisms, it appears that, reduced to their lowest terms, they must consist of two atoms of a chemical element arranged with the simplest definite relation to each other. This should be the beginning of the lowest form of life, and we also found this to be the lowest ideal organism. It is represented by the ultimate molecule, which may be the nucleus or beginning of a crystal of a chemical element.

The conclusion here reached by deduction will no doubt be at first regarded with astonishment, and without inductive proof it is not expected that this view can be received except by those already prepared by a knowledge of such proof; but the evidence which the writer has seen on the subject is such as to convince him that the same conclusion may be reached by other and more satisfactory methods of research. This method of first presenting the subject has, however, been selected because it seems to show, from a study of the somewhat imperfect idea of life, what is necessary to its perfection. Consideration of the subject from this stand-point first, may prepare some minds to study it thoroughly without the prejudice which might otherwise prevent; and, finally, because the building up of any structure is greatly facilitated by first perfecting a definite plan, so that the position and relation sustained by the component parts may be readily seen as soon as each is presented.

It is believed that the generalization indicated may be made and established with great advantage to the study of biology. The plan of the creation or evolution of living organisms is thereby rendered much more simple and easy of comprehension, as may perhaps be made to appear at some future time.

Whether the lowest living things can be properly called organisms, will depend upon the definition of the words organism and organ. According to the ordinary definition, an organism is a body consisting of mutually dependent parts having functions, and an organ is one of such parts. The word organ, as appears from the above quotation, has heretofore been applied only to visibly distinct parts having functions, &c., although the definition; in our standard dictionary is similar to the one given above, and has no such requirement.

The standard definition will allow of its use in the extended sense that I wish, viz., to denote any mutually dependent parts of definitely-combined matter having separate functions, whether or not the part or function be capable of demonstration to the single sense of vision. It is essential to a right understanding of scientific problems, that the terms employed should have a precise meaning. If the words organ, organism, and organized, cannot appropriately be used in connection with all definitelycombined matter, and must, on account of old associations, be restricted to such compounds as have visible distinctions of parts, then it would seem to be advisable to invent new terms which shall, in a word, or as concisely as possible, embrace all such compounds, and thereby render easy this comprehensive and general view. But if this be done, the old words left as heretofore, there is then no well-marked limit or beginning of organization, for what is visible to one, under certain circumstances, may not prove so to others, and again the limit would vary with the magnifying power used. If however, the old terms (organism, &c.) be retained and thus defined, it will still be easy to distinguish between visible and invisible organs; the invisible orgaThe ideal lowest form of life and the lowest organ-nization may be denominated primary, as it undoubtism we have found to consist of "two atoms of an edly is, to vegetable and animal organization. In my elementary substance arranged with the simplest opinion, the science of biology will at present be best definite relation to each other," and we know that facilitated by thus extending and defining the there are existing in nature such combinations of words used. The important reason for wishing matter. In a previous part-"The Order of Crea- thus clearly to define and extend their meaning is tion of Living Beings "-it was pointed out that their to collect under one general view the prominent creation could be traced back to the chemical ele- phenomena attendant upon matter arranged in defiments as its starting-point. From this lowest form nite compounds. At present certain highly-complex, of life there is a constantly-ascending scale up to definite compounds are called organisms; certain human life. From this simplest organism there is others, less complex, living things, but are not cona constantly-increasing complexity of combination sidered organisms, because not having visible and organization up to the human organism. An organs; others, nearly as complex as these last, attempt will be made to show that the phenomena are attendant upon changes occurring in the simpler combinations which may be called primary organisms resemble, and are in fact similar to, those which are recognized as characteristic of living beings. We shall find how perfectly they accord with our definition of life.

According to the ordinary definition, an organism is a body consisting of organs, or mutually depen dent parts having functions. The lowest organism should consist of the least number of mutually dependent parts, having functions of the simplest character.

The least mutually dependent number would be two-and, as the smallest portion of matter imaginable is called an atom, nothing less than that could be conceived as having a function; and, as the functions of two precisely similar atoms would be least contrasted, and of the simplest character, the lowest organism should consist of two equal atoms organized or arranged, so that its existence as an organism would depend upon the functional activity of each, which might consist in their mutual attraction for each other. This would be the case in a molecule consisting of two atoms of a chemical element. And, as the atoms of an elementary substance are alike, their functions would be equal. We notice, next, that living bodies have a definite composition; they consist of definite proportions of certain elements definitely arranged. Arrangement implies relation, and would require, at least, the presence of two units. The simplest definite proportions would be equal, and as the least portion of matter is the atom, a definite compound reduced to its lowest terms should consist of two equal atoms arranged with the simplest definite relation to each other.

Beginning the subject inductively, let us first consider organization; that being an acknowledged characteristic of at least the higher living beings, and the first one mentioned in our analysis.

The word organism has heretofore, I believe, only been applied to those compounds which have visible distinctions of parts; leaving out, among those which have not such distinctions, some which were nevertheless considered living. "The lowest living As to form, we should expect to find the lowest things are not, properly speaking, organisms at all; life, having definite form, of the greatest simplicity. for they have no distinctions of parts, no traces of Complexity of form results from complex arrange- organization "-(Herbert Spencer). Before the miments of heterogeneous elements; the greatest sim-croscope revealed its world of living beings, the plicity of form will result from the simplest arrange- general idea of organisms probably included only ment of like elements. Simple definite forms are those whose organs or distinctions of parts were found in crystals of the chemical elements, gold, visible without its use; some minute moving bodies copper, iron, sulphur, phosphorus, carbon, &c., which were no doubt by some considered living, although usually crystallize in simple cubes or octahedrons. their organs could not then be distinguished. AfterGrowth is an increase of the elements composing ward, with the aid of the microscope, their organs the body, in the proportion and having the arrange- were plainly seen, as were also myriads of other ment proper to it. The simplest requirement for organisms. With the microscope other minute growth would be the smallest equal proportions of moving bodies have been brought to view, and are one element with the simplest definite atomic now considered living, although their organs canarrangement. This might be the case in bodies not be distinguished. We have again reached a consisting of one element. point where a still higher vision is required to enable us to see a mutual dependence and distinction of

The changes occurring in a living body to a cer

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called organic, because heretofore only found in organisms; others still complex, are called inorganic chemical compounds. minent fact connected with all these structures is, their definite composition and definite atomie or molecular arrangement: and the certain and regular phenomena attendant upon their experience of certain conditions are believed to be in consequence of this definite composition. This broader generalization seems to me to be useful, taking in as it does all definite combinations, and distinguishing them from amorphous, non-arranged, or, according to my view, unorganized matter. If this be done, as heretofore indicated, the beginning of the simplest organization will be where the first two atoms unite with a certain or definite relation to each other, to form a definite compound. In accordance with the foregoing views, life is conceived to be manifested by all organized matter, the kind of life depending upon the character of the organization.

Among scientific men, at the present time, the tendency is to look for the lowest organization and the beginning of life among the protean compounds; and protoplasm is the name given to what many now consider as the connecting link between inorganic matter and living organisms. It seems to me, however, that they are not searching deep enough; that protoplasm is about midway between amorphous matter and the highest organisms, and cannot profitably be considered as the beginning of life or of organization, although it may be, as the beginning of the two highest organic kingdoms-the

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