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THURSDAY, JANUARY 1, 1874

would not secure Professors of high scientific qualifications, to whom the permanency of the scheme has to

be assured. Besides the stipends of the Professors, THE YORKSHIRE COLLEGE OF SCIENCE

sundry annual expenses for working and maintenance

will be required, and these will be paid out of the general N OW that a scheme for a College of Science at Leeds | fund. The Committee therefore appeal for contributions

has been all but completed, under the chairmanship upon a generous scale commensurate with the importance of Lord F. C. Cavendish, M.P., it seems somewhat sur- of the proposed scheme. This appeal has been well prising that such an institution in connection with York- answered already ; but we hope that the Committee will shire has not been thought of long ere now. It is the largest not rest until the whole of the original scheme has been county in England, carries on a greater variety of indus- realised. tries ali more or less dependent for success on the results of The Committee refer to the sum raised for the Newscientific research, and boasts of a larger number of local | castle College of Science, 22,0251., with an annual conscientific societies and field-clubs than any other county tribution of 1,000l. from the University of Durham, and in the three kingdons, as we have shown in our articles say with justice, that, considering that the wealth of the on that subject. However, “better late than never ;” and district over which the benefits conferred by the Yorkshire to judge from the prospectus and subscription lists, a very College of Science will extend is at least equal to the fair start is likely to be made. The scheme proposed by | Newcastle district, it is to be hoped that the public.spirit the committee formed at Leeds in 1869 involved an ex- of Yorkshireinen in behalf of the College will be as freely penditure of 100,000l., but it is not intended at present to l expressed. carry out the whole of this scheme, but to commence on To the Owens College, Manchester, the sum of 13,500l. a smaller scale in temporary premises and with a limited has been contributed by the engineering profession tonumber of professors. We have no doubt, from the wards the endowment of the chair for Engineering ; and hearty way in which the proposal has so far been met, the hope is entertained that towards the endowment of that the college will be a success, and that ere long it will the Professorship in that subject in the Yorkshire Colbe possessed of a handsome building of its own, with a lege of Science, aid may be forthcoming from a similar full staff of professors.

source. The chair for Chemistry has also peculiar claims From what follows, it will be seen that the teaching for support upon the manufacturers of the county whose will have a practical or technical aspect, having regard business requires the aid of chemical science. to the processes connected with the multifarious arts and Arrangements will be made for the establishment of manufactures which occupy the large population of York- scholarships at the College. All donors of 500l. and up. shire. In the midst of an eminently practical people, there wards towards the College funds will be entitled to nomican be no fear of this consideration being neglected, but nate to a free studentship for a term of years. we hope that in the long run the claims of pure science will It is proposed to vest the government of the College in not be overlooked, for it is every day being more and more a board of governors, consisting of (a) all subscribers of clearly proved that a preliminary training in pure scien 250l, and upwards ; (6) fifty governors elected by the tific research is the best introduction to a "technical ” general body of subscribers ; (c) two professors elected education; and very many of the industrial applications by the professorial staff. The governors shall hold two of science have been found out by students who took no meetings in the year, shall appoint trustees, shall audit thought of the practical issues of their investigations. the accounts, shall receive the annual report from the There is more than one institution in America which council of the College, and shall constitute a court of might, in this respect, be taken as models for a technical appeal in certain cases. The ordinary administration college.

shall be in the hands of a body called the council. This The Yorkshire College of Science, the Prospectus shall consist of fifteen members, including a chairman, to tells us, is intended to supply an urgent and recognised be elected out of and by the governors. want, viz. :-Instruction in those Sciences which are | One of our wealthy City Companies, the Clothworkers' applicable to the Industrial Arts, particularly in their Company, we are glad to see, has generously come forrelation to Manufactures, Engineering, Mining, and ward in the interests of the College as well as in the Agriculture. It is designed for the use of persons who | interests of the particular branch of manufacture with will afterwards be engaged in those callings as foremen, which the Company is connected, by endowing a Profesmanagers, or employers; and also for the training of sorship of Textile Fabrics with 300l. a year. The subscripteachers for ordinary Science Schools and Classes. tion of the coal-owners alone amounts to some thousands

To carry out the object of the College, it is proposed to of pounds, and we have no doubt, when the time comes to establish Professorships in (1) Chemistry and its appli extend the sphere of the College and to give it a permanent cation to Metallurgy, Manufactures, and Agriculture ; building of its own, this wealthy class will see it to be their (2) Civil and Mechanical Engineering ; (3) Physics and duty largely to add to this subscription. We hope also Mathematics ; (4) Geology and Mining.

that others of our City Companies will see it to be their The Provisional Committee seem to have right notions interest to lend a helping hand to the young institution. as to how scientific men ought to be treated. To obtain There are several such technical institutions on the Conthe services of eminent scientific men, they say, the pay- tinent, and it is on this account that in several respects ment to each Professor cannot be less than 300l, per Continental manufactures are much superior to those of annum, in addition to a proportion of the students' fees. A Britain. Let us hope that this may not be much longer precarious income, if raised by annual subscriptions, the case, but that by the establishment of the Yorkshire

VOL. IX.-No. 218

III

College of Science, and similar institutions in other dis- | number of trials, made with the help of Mr. R. Knight, tricts, all who are in any way connected with our arts and a simple arrangement has been completed, which answers manufactures may be trained to work on a method so satisfactorily in showing the behaviour of a ray of light really scientific that Britain shall in this, as she certainly under the various circumstances of ordinary refraction. is in some other respects, be foremost among the Pieces of a thick-piled velvety plush known as “ imitation nations.

sealskin” are cut out to represent the sections of a thick plate, a prism, a convex and a concave lens, and glued on

to smooth boards. The runner consists of a pair of boxREFRACTION OF LIGHT MECHANICALLY wood wheels mounted loosely on a stout iron axle, and is ILLUSTRATED

trundled across the board, or still better, the board itself TN preparing an elementary lecture on Light, intended 1 to be given at the Taunton College School, I have

Fig3

l'iy, i had to consider how best to explain the somewhat abstruse principle of optical refraction. It is true that Sir John

1 Herschel, in the sixth of his “Familiar Lectures on Scientific Subjects,” giving the explanation of refraction on the undulatory theory, describes it as being “exceedingly simple.” The fact is, however, that it involves conceptions of wave-motion, difficult for any but advanced L EIL---students, and even they feel grateful to the eminent physicist for the help afforded by a familiar illustration with which he follows it. He desires his readers to is tilted up, and the runner let go in the proper starting imagine a line of soldiers marching across a tract of direction. The following figures show the path of the country divided at a straight boundary into two regions, wheels, always from right to left of the page. the one level ground suited for marching, the other rough In Fig. 1, the runner starting from A, enters the recand difficult to walk over. Now if the line of soldiers tangle of velvet at B, where its left wheel being first remarch with their line of front oblique to the boundary, tarded, it shifts round into the direction BC, till it reaches the men on the side just engaged in the heavy ground C, where the left wheel first emerging gains on the right,

so as to bring back the runner to the ultimate direction CD. This illustrates the refraction of a ray of light in entering and quitting parallel plane surfaces of a resisting medium, such as a plate of glass. When the runner enters at right angles to the boundary, its direction is of course unchanged, as with the ray of light.

Fig. 2 shows the path ABCD of the runner across a triangle, corresponding with the course of a ray traversing a prism. Also, by causing the runner to enter at about a right angle near E, a direction is given to it which, if the

surface of the board and the triangle were similar as to will be retarded as soon as they cross into it, so that if

resistance, would make it emerge near F, at a small angle the line be kept unbroken, the consequence must be a change of front, which will leave the whole body of men

Fig.5 marching across the heavy ground in a new directionin a word, their direction of march will have been refracted. Now the light-waves emitted from a radiant

E -- -point being compared to the circles spreading from a stone thrown into a pond, it is easily understood how a sensibly straight portion of such a light-wave, passing obliquely from one medium to another of different resistance, will be refracted in a new direction. This simple conception of change of front is at once apprehended by to the side. But the left wheel passing on to the smooth the learner, to whom refraction thenceforth ceases to be a surface gains so much on the right wheel still in the molecular mystery, and becomes an intelligible mechani- velvet, that the axle slews round, the left wheel re-enters th cal act dependent on the resistance of the two media velvet, and the runner goes off in the direction FG, thus and the form of their limiting surface. Probably no point illustrating the total reflexion which takes place when a in all Herschel's lectures has fixed itself in the memory | ray of light is directed to emerge very obliquely from a of so many intelligent readers.

more into a less resisting medium, as from a glass prism In following up the train of thought started by Sir or a surface of water into air. John Herschel's comparison, it occurred to me that an The action of the double-convex lens in causing parallel instrument made to perform refraction mechanically or divergent rays to converge is shown by the path of the would be useful in teaching optics, and that such a con- runner in Fig. 3, which requires no further explanation, trivance would only require a pair of wheels running on nor does that corresponding to the divergent action of a table, into and out of a resisting medium. After a the double-concave lens, Fig. 4. By starting two runners

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II

at once from the right-hand side of the board, so as to notes by the reporter, pp. i.-ccxxxvi. An article on “Fish traverse the upper and lower parts of the convex lens, as Food, or the reputed Origin of Disease,” an Enumerathey are made to run into one another, thus illustrating tion of the Indian freshwater fishes, and Notes on prethe meeting of rays in a focus.

| serving specimens of fish, conclude the volume. Lastly, by using two runners with wheels of different Europeans who have formed favourable ideas respectdiameters, as the refraction depends on the resistance to ing Indian rivers and their abundance of fishes from the the wheels by the velvet, the apparatus may be so inclined accounts which so frequently enliven the sporting papers as to show plainly their consequent difference of refrac- l of the day, will find them rudely dispelled by this report. tive angles. The courses of the two are seen in Fig. 5. It is true that not a few of the resident officials deny the This experiment, however, requires some nicety of ar decrease of fishes, and deprecate legislative interference rangement

altogether. Thus, for instance, the Commissioner of the Now the separation of rays of different refrangibilities Agra Division writes that there is no reason to apprehend by a prism being due to a like cause, this experiment that any wholesale destruction of fish goes on in these serves to illustrate mechanically the decomposition of parts. A close-time might no doubt be introduced by white light. Let the large-wheeled runner represent law for the protection of fish during the breeding season, the red ray, and the small-wheeled runner the violet ray, but it does not appear to him that it would be easy to the principle of the prismatic spectrum becomes at once carry out such a measure, or that there is any compenevident.

sating object to be gained ; that “it is a useful maximFor the information of any who may wish to reproduce de minimis non curat lex-minute legislation is unbefitthis simple apparatus, I may state the dimensions I have ting our position in this country, and more likely to exfound convenient. The wheels may be 18 in. and 2 in., with pose our Government to ridicule than to any results of rounded edges, mounted on a nearly half-inch iron axle, important benefits to the people ;" “it is in the highest turned down to in. at the ends. The boards may be 2 ft | degree undesirable that the public mind should be dis6 in. by 1 ft. 6 in., with velvet on each side. It is conve. | turbed by gratuitous interference on the part of an alien nient to place the velvet nearer to one end of the board administration, enforced by not very trustworthy agency." to leave room at the other for starting the runner; and On the other hand, the Inspector adduces such incontrocare must be taken to cut the velvet so as to present a vertible evidence in favour of the conclusion he has arrived good resisting surface, as this varies with the direction of at, that we can but agree with him that in numerous disthe pile. In using the apparatus for teaching, care intricts the freshwater fisheries are in danger of being manipulation is required to neutralise the defects of the utterly destroyed, and this must appear to call for speedy texture. Some kinds of " Utrecht velvet,” to be had from interference by the Government all the more, as those the upholsterers, are more uniform than the “ imitation districts are among the most populous, in which this seal-skin," and thus work more equally, but their effect is article of food can be least spared. not so striking. Wet sand will answer equally well with Naturally one looks first for the causes by which the the velvet, if metal wheels be used.

Indian fisheries are said to have been thus reduced ; and EDWARD B. TYLOR it is not very flattering to be told by the author that this

disastrous effect has been caused by the change from the

Native to the British rule. He states that, under the forTHE FRESHWATER FISH OF INDIA AND

mer rule, fisheries formed royalties mostly let out to conBURMAH

tractors, who alone in the district possessed the right to Report on the Freshwater Fish and Fisheries of India

sell fish, and that they permitted the people, on payment, and Burmah. By Surgeon-Major Francis Day, F.L.S.

to capture fish for their own consumption ; that the men and F.Z.S., Inspector-General of Fisheries in India.

who followed the occupation of fishing formed distinct 8vo. (Calcutta, 1873.)

crafts or castes, exercising their calling with certain reIN the introductory part the author states that the pre strictions and regulations. Under British rule the renting I sent report is the result of investigations commenced system was abolished; with the most philanthropic by him in the year 1868, into whether a wasteful destruc- intentions, the British gave to the people liberty to fish tion of the fresh water fisheries is or is not occurring in when and where they pleased ; where everybody could fish, India and Burmah. He comes to the conclusion that a j fishing ceased to be a distinct calling ; breedingfish were wasteful destruction of fish is going on to a very great captured without regard to season ; and when the supply extent, that these fisheries are more and more deterio-l of larger fish commenced to fail, it became the practice rating, and that immediate legislation is called for, tol to catch undersized fish and fry. Add to this, that a prevent the entire failure of a most important article of number of irrigation weirs and dams were erected, prefood.

venting the fish from resorting to suitable spawning beds, The steps taken by the Inspector-General to ascertain that fixed engines for the capture of fish are now used, the facts on which he bases his report were twofold. where previously they were never permitted, and the He personally inspected districts of various parts of the natural result is the lamentable state as represented by Indian Empire, and supplemented his own observations the Inspector. by collecting the opinions of European and Native offi We need not enter at present into the remedial meacials, to whom he addressed a series of questions bearingsures provisionally proposed by Mr. Day. His proposals, upon the subject. Accordingly the book before us is as well as the opinions of his opponents, will no doubt divided into two parts :-(1) The report proper, pp. 1-118; | find due consideration on the part of the Indian Governand (2) A résumé of the answers returned, with marginal | ment. But I will not conclude this notice, without alluding to one or two of the reports of European officials, required is but very elementary, as the proofs of the which will show that, however weighty their evidence formulæ are only given when they present no complex may be as regards the practical side of the question, their arguments,” but it should perhaps have been added that, opinions in scientific matters are open to criticism. Mr. even in cases where the apparatus is simple, outlines of Day had drawn attention to the destruction of fish by the mode of performing an experiment are generally various kinds of crocodiles, very properly recommending alone supplied, the teacher being left to explain to his that rewards should be paid for their eggs. To this one | pupils the niceties of arrangement and manipulation. of the officials replies :-"Waging war against such fish- Regarded as a syllabus of a course of physics, the book destroying animals as crocodiles appears to me absurd. ) is incomplete, no account, for instance, being given of I have no doubt at all but that a general destruction of Favre and Silberman's Calorimeter, or, with the exception crocodiles would directly frustrate the end hoped for by of saccharimetry, of experiments on polarised light; and their destruction. Their very presence in numbers, it if the author's plan be thought to justify the exclusion of being given that they live on fish, shows that the supply these, the same reason can hardly account for the omisof fish is abundant, which is all that anyone requires, and sion of methods for determining melting points, or the nature in these matters, if left alone, keeps the balance specific gravity of substances whose constitution is altered even, and resents interference." This is exactly the same by exposure to the atmosphere, or the ratio of the inview as that held by the modern advocates of a general tensities of the illuminations produced by two sources of preservation of birds, who would preserve even such as light, or of all experiments relating to the capillary elethe sparrow-hawk and cormorant, and who forget that vation of liquids in fine tubes. nature itself, in distributing animal life, does not always! It is, however, as a collection of formula that “ Physical consult the convenience of man. In India, the presence Measurements " is likely to prove most useful, and from of tigers, poisonous snakes and crocodiles, would appear this point of view the “ Introduction” seems to us one of to prevent this doctrine from being generally adopted by the best parts of the book. It contains the rules for the European community. Another official refers to a finding the mean and probable errors of a set of observa“ very exhaustive and carefully drawn up report” from a tions, and for determining empirical constants by the Civil Surgeon in his district ; this report is accompanied method of least squares, together with hints as to how to by a list of the freshwater fishes, in which occur some shorten the labour often wasted in the calculation of corspecies with Buchanan-Hamilton designations, others rections ; points on which a short practical treatise like with Latin terms derived from a dictionary, a cod-fish, a that here provided will afford great assistance to those john dory, and “a very common fish, the scientific name who are not mathematicians. of which is supposed to be Lacerta scincus !!Can anyone. The sections devoted to weighing and measuring are doubt after this that a comprehensive and well-illustrated | full and good, especially those which relate to the use of hand-book of Indian Freshwater Fishes with an introduce the balance, but heat and light are not treated of in an tory treatise on the elements of Ichthyology is called for ? equally satisfactory manner.

ALBERT GÜNTHER

The experiments on these subjects which are described are not numerous enough to satisfy the requirements of

large laboratories. Moreover, sufficient attention seems KOHLRAUSCH'S "PHYSICAL MEASURE

scarcely to have been paid to the fact that students should . MENTS

be encouraged to apply corrections to the results of experiAn Introduction to Physical Measurements, with Appen ments which they perform, not so much on account of

dices 01 Absolute Electrical Measurement, &c. By | the more accurate numerical values thereby obtained, as Dr. F. Kohlrausch. Translated from the Second Ger- for the sake of the excellent practice the necessary obserman Edition by T. H. Waller, B.A., B.Sc., and H. R. vations often afford, and the insight gained into the Procter, F.C.S. (London: J. and A. Churchill, New theoretical principles on which they are founded. A case Burlington Street, 1873.)

in point is the omission in the article on the DeterM ESSRS. T. H. WALLER and H. R. Procter have mination of Specific Heats by the Method of Mixtures of

IVT furnished us with a translation of the second any account of the correction employed by Regnault for edition of Dr. Ko''rausch's “Physical Measurements," to the loss of heat by radiation. which they have a lded several useful Appendices and We miss all mention of the optical bank, and the Tables.

mathematical expressions for results involving the deterTheir work is intended to serve as a text-book for mination of distance in terms of differential measures on students in experimen: :l physics, and consists mainly of a that instrument. In the article on the spherometer, which collection of the formulæ used in correcting and applying is in other respects incomplete, we see no instructions for the results of the simpler experiments in weighing and finding the radius of a spherical surface too small to permeasuring, heat, light, electricity, and magnetism, accom- mit the instrument to be placed upon it ; and omissions panied in each case by such an account of the method of | are made in the pages devoted to the spectrometer, the observation employed as may suffice to render them intel goniometer, and elsewhere, which combine to render the ligible.

section on Light very imperfect. The limits which the author assigned to himself are Nearly one half of the book is given up to Electricity very clearly laid down in the Translators' preface, in which and Magnetism, subjects in the study of which assistance we are informed that “descriptions of apparatus are but can be more readily rendered by the method of treatment rarely given, as students mostly have instruments provided here adopted than in those we have been discussing, as for them," and also that “the mathematical knowledge numerous mathematical formulæ are required which are in many cases obtained by calculations beyond the grasp an account of the diseases to which it is most liable. of the less advanced pupils'; and the Translators have con These are replete with practical detail that must be most siderably improved what was already good by several

valuable to the many who spend such large sums on preAppendices, among which one of the most important is

serving game, and to those who have the actual superin

tendence of the coverts themselves. Particular attention that on Thomson's electrometer. Some preliminary

is drawn to the great difference between birds, like the sections are devoted to the reduction of observations common Fowl (Gallus bankiva), which are capable of made with the mirror and scale to angular measure, to domestication in the true sense of the word, and the the determination of the position of equilibrium and time Pheasants, which, though individuals are frequently of oscillation of a magnetic needle and similar topics,

known to become tame, can never be really domeswhile the methods of reading the various magnetometers

ticated ; even the young ones taking to the woods on the

earliest opportunity, whilst the opposite inherent pecuand galvanometers, and the measurement of resistance | liarities of the poultry have given rise to the proverb-and electromotive force, are afterwards discussed.

“Curses, like chickens, come home to roost." AltoOn the whole the principal fault we have to find with gether this work supplies a long-felt want, and its perusal the book is a want of fulness, especially in the earlier por- | will well repay anyone who takes it up. tions. It aims at supplying a want already felt, and which will become still more pressing as the number of those who make some progress in the study of Natural

LETTERS TO THE EDITOR Science increases, and we are not aware of the existence [The Editor does not hold himself responsible for opinions expressed of any manual which gives the information contained in

by his correspondents. No notice is taken of anonymous it in an equally compact and handy form ; while the

communications.] tables, thirty in number, which fill the concluding pages,

Wasps will often save time and trouble to those engaged in labo

Perhaps it may be of interest to some of your readers, who

make entomology their study, to know that the wasps in a nest ratory work. Although, then, as we have already

about a mile from this were still tolerably active on the 13th of pointed out, we consider it capable of very considerable this month, when my attention was attracted by the loud buzzing improvement, yet probably most teachers of Experi

of three or four wasps at the entrance, apparently ventilating it

with their wings after the manner of bees. mental Physics will obtain some useful hints from its

I again visited the

place on the 23rd. There were at first no signs of life outside ; perusal, even if they do not adopt it as a text-book for but stamping on the ground above caused a considerable number their pupils.

A. R. to come out after a minute or a minute and a half and hover in

the air above the entrance. I attribute this unusual circumstance to the mildness of the season (the minimum temperatures having

been 26° in October, 25o. in November, and 29° on the roth and OUR BOOK SHELF

IIth of December, and the 13th having been mild, and so also

the 23rd) and the bad conducting power of the nearly cut out Pheasants for Coverts and Aviaries. By W. B. Teget

peat bog in which the nest was situated. meier, F.Z.S. (London: Horace Cox. 1873.)

Birr Castle, Parsonstown, Dec. 24, 1873

ROSSE ANY work on animals which appeals to so many different human weaknesses as the Pheasants, must be popular

The Potato Disease and Lord Cathcart's Prize if the least effort has been made to do the subject

No one acquainted with botanists and botanical science can justice. The one before us has merits which make it

feel surprised at the decision of the committee in this matter, peculiarly acceptable. It is by the hand of an author

and it must be confessed that, however well meant, the offer of who has devoted his life to the careful study of the na

the rool. prize was a great mistake which has only ended in protures and habits of the Gallinaceous birds and Pigeons,

ducing ninety-four unsatisfactory essays and the loss of a year. and who has long since made himself well known by

Little else could have been expected, for the Council of the works on some of the genera, which have become the | Royal Agricultural Society must surely be aware that the men standard literature of the points on which they treat. (in this country at least) who are competent to write anything In the handsome volume before us Mr. J. W. Wood's now on the subject could certainly be counted in units, and these excellent and truthsul illustrations add greatly to its men could not enter into the competition for more reasons than value, though the absence of coloration has made it more one, not the least being the loss of status such a proceeding would

entail. than difficult in some cases to produce an approach to the gorgeous appearance of some of the species depicted.

It appears to me that the committee have even now hardly hit

the right nail upon the head in recommending a grant of money Among those that suffer most from this deficiency, are

to “some competent mycologist” to investigate the life history of the Japanese Pheasant (Phasianus versicolor), whose

the fungus during a certain period of its life. If the investigachief beauty consists in the richness and delicacy of the

tion is carried on hy any one man it is sure to end in failure. It shades of its plumage, and the Golden Pheasant (Thau

would be far better for the committee to recommend that melia picta), with its ally, the Amherst Pheasant (T. am

five or six competent botanists should each write an essay herstiæ), whose resplendent hues even the best artist finds on the subject from his own point of view, each essay it difficult to represent. The Reeves' Pheasant (P. reevesii), to be published in the Society's journal. There are many and the Eared Pheasant (Crossoptilon mantchuricum), reasons why this would be best. "I will give one. Payen however, form excellent and most truthful pictures, colours has figured and described certain ciliated bodies found in spent in them not being such important features. Mr. Teget potatoes, and which Berkeley and other botanists have looked meier, besides describing each of those species which are

upon as the probable resting-spores of the Pronospora. Mon.

tagne has referred these same bodies to the Sepedonici, whilst I the love of the sportsman and the pride of the aviary,

am by no means sure that the objects do not belong to the Stil. devotes the earlier part of his work to the discussion of

bacei, and are no other than Volutella ciliata. However this may points of great practical interest. After a short history of

be, I have met with the last in spent potatoes in immediate con. the Pheasants as a family, from which it is clear that they

nection with the Peronospora itself. Where competent observers were introduced into this country from Asia Minor, the

differ in opinion it is better to get the views of all. It would be native home of the common Pheasant (P. colchicus), as

very unwise to restrict the observations to any particular period early as the reign of King Harold, and probably by the l of the growth of the plant, and very little would be added to our Romans, a series of chapters is given on the management knowledge were the resting spores themselves found; for, resting of the bird in preserves and in confinement, together with spores or no resting spores, it is an ascertained fact that the living

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