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LETTERS TO THE EDITOR.

(The Editor does not hold himself responsible for opinions expressed by his correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscripts intended for this or any other part of NATURE. No notice is taken of anonymous communications.]

Archebiosis and Heterogenesis.

THE Columns of the daily papers have during the last two weeks contained many references to the question of the origin of life. One of the most recent utterances has been that of Lord Kelvin, who has roundly declared himself an unbeliever in the natural origin of living matter either in the present or in the past. We must suppose, therefore, that in reference to this question he is content to believe in miracles.

Prof. Ray Lankester and Dr. Chalmers Mitchell, however, proclaim themselves, as followers of Huxley, believers in evolution generally, and in the natural origin of living matter in the past. They, like many others, refuse to believe that it takes place at the present time, because undoubted proof of its occurrence cannot be produced by laboratory experiments. The uniformity of natural phenomena would certainly lead us to believe, as Sir Oliver Lodge has intimated, that if such a process occurred in the past, it should have been continually occurring ever since--so long as there is no evidence to show cause for a break in the great law of Continuity. Certainly no such evidence has ever been produced, and if the origin of living matter takes place by the generation in suitable fluids of the minutest particles gradually appearing from the region of the invisible, such a process may be occurring everywhere in nature's laboratories, though altogether beyond the ken of man.

My point may be illustrated thus. Bacteriologists all over Europe and elsewhere have been working for the last thirty years by strict laboratory methods, and notwithstanding all that they have made out and the good that has thereby accrued to suffering humanity, they have apparently never yet seen the development from Zooglea aggregates of Fungus-germs, of flagellate Monads, or of Amoebæ. If, however, they would only examine what goes on in nature's laboratory when a mixed bacterial scum forms on suitable fluids, they would have no difficulty in satisfying themselves as to the reality of these processes. I described such processes in your columns in 1870, more fully in the Proceedings of the Royal Society in 1872, and finally in my "Studies in Heterogenesis " (pp. 65-84, pls. vi. and vii., Figs. 53-71). Even during the last week I have again obtained photomicrographs demonstrating the origin of flagellate Monads from Zooglea aggregates forming in a bacterial scum, and if you will admit an illustrated communication on this subject to your columns, proving by such a test case my position as to the reality of heterogenesis, I shall be happy to present it, and to show that something beyond the recognised strict laboratory methods of the day is needed if we are to fathom some of nature's deepest secrets.

The councils of the Royal and Linnean Societies are guided in the acceptance of papers by referees who are wedded, on biological questions, to laboratory methods. It is useless for me, therefore, again to attempt to submit such a communication to them. Their referees (probably not having worked at such subjects themselves) would not advise the acceptance of the paper, and my communication might simply be consigned to their archives. The Royal Society "for the Promotion of Natural Knowledge 5, occasions would not even allow me to submit my views to the consideration of, and discussion by, its fellows. In these circumstances, Sir, I appeal to you, in the interests of science, to allow me to send you an illustrated paper proving, so far as such proof can go, the heterogenetic origin of Hagellate Monads and of Fungus-germs.

Manchester Square, October 31.

on two

H. CHARLTON BASTIAN.

[IN reply to Dr. Bastian's appeal we will print his communication, and also any important replies from competent workers on the subject which may be sent to us.-ED.]

Average Number of Kinsfolk in each Degree.

I was glad to read the first paragraph of the reply by his mistake, but I cannot allow the second paragraph to Prof. G. H. Bryan to my letter, in which he acknowledges pass without protest, in which he says "the discrepancy can be accounted for more simply still" in a way he describes. I do not wholly understand his present view, but only enough of it to be assured that it is vitiated by some fundamental misconception. In these circumstances it is best to re-state my original argument in different words. We agree to start on the assumptions that boys and girls are on the average equally numerous, and that all other conditions are to be ignored. Then, if an individual be taken out of a family of 2d children, 2d-1 children will be left, of whom d- will, on the average of many experiences, be girls and d-will be boys. The sex of the individual who was taken out in the first instance is quite unimportant; the result will be the same whether that individual be a boy or a girl.

Prof. G. H. Bryan thinks, if I understand him rightly, that the sex of the individual in question is of importance. Some persecuting demon must have again caused my pen to write and my eye to overlook an absurdly erroneous figure in my last letter. The faulty passage runs "... is 80 (=2×16, as it should be)"; the 16 ought to be replaced by 32. It is intended to be quoted from the right hand column of line (5) in the table which accompanies that letter. FRANCIS GALION.

Misuse of Words and Phrases.

IN the preface to my book on "Cubic and Quartic Curves "I have stated my views on the matters referred to in the last paragraph of T. B. S.'s letter. I am a strong advocate of the use and, if necessary, the invention of words of classical origin to express new ideas, and I consider the phrase self-cutting inelegant.

My objection to the phrase non-singular cubic or quartic curve is that no such curves exist, since Plücker has shown that all algebraic curves, except proper conics, possess a determinate number of singularities. Thus anautotomic quartics possess 52 simple singularities, viz. 28 double and 24 stationary tangents. It is also possible for such curves to possess compound singularities, formed by the union of one double and two stationary tangents.

With regard to the use of an, the rule is that before a word beginning with a vowel an is to be used instead of a for the sake of euphony, but when a word beginning with a vowel is pronounced as if it commenced with a consonant, a must be used instead of an. The phrases such an one, an uniform rod, an wonderful sunset, an yew tree, are all equally incorrect. A. B. BASSET. November 4.

The Coming Shower of Leonids. THE pretty abundant shower of Leonids witnessed last year encourages the hope that a fairly rich return may be observed this year. There will be no moonlight to interfere with the brilliancy of the display should it occur, and the most probable time of its apparition will be before sunrise on November 15.

In 1903 the maximum occurred between 5 and 6 a.m. on November 16, and, allowing for leap year, the ensuing maximum should take place on November 15 at about noon. The shower seems likely to be observed to the best advantage at American stations, as in 1901, but it should be carefully watched everywhere, and with a special view to ascertain the hour of greatest abundance.

It is to be hoped that some further attempts will be made to determine the place of the radiant by photography. We have already a sufficient number of eye observations of the position, and the work of ordinary observers will be better directed to counting the number of meteors visible at regular intervals during the night, and registering the most brilliant objects. The meteors from other showers should also be noted, and especially any conspicuous Taurids that may appear. The latter by their slow long flights and yellow trains are readily to be distinguished from the swiftly moving Leonids with their green streaks. W. F. DENNING.

OWING to the large numbers of shooting stars visible on the night of November 15, 1903, the expectation of witness

ing a meteoric spectacle on perhaps a more extensive scale will probably be revived on the near approach of the Leonid epoch of 1904. Reasons have already been given for supposing that last year's display was connected by the nineteen years' period with a very similar phenomenon observed on November 13, 1865, the interval between the two events representing two complete revolutions of the meteoric cycle. The present epoch, therefore, which is thus associated with the historic meteor shower of November 14, 1866, will be hable to reproduce its brilliant prototype, though only to a limited extent.

The anticipated shower, however, if it takes place, will not occur on the night of November 14, as it might naturally have been expected to do, owing to 1904 being a leap year. The meteor-swarm, according to calculations made by the present writer, has undergone considerable retardation since 1903, and as a result of this perturbation the Leonid meteor shower becomes due in 1904 on the night of November 15. It is on the latter night, therefore, that the maximum will take place, whether it culminate in a shower or not. will occur, however, on November 14, 15h., an interesting miniature meteor display. The shower on the night of November 15, though not so intense, will be more extensive than that of 1866, as maxima fall due at 9h., 12h. to 15h., and 17h. 30m. G.M.T. JOHN R. HENRY.

The Definition of Entropy.

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Let the available energy of any system at any instant relative to a refrigerator of temperature T, be defined by the condition that it is the maximum amount of energy that could be obtained from the system at that instant by reversible thermodynamic engines working between the stem and the refrigerator T., the remaining portion of the energy being, of course, called non-available energy. Then in any change of the system the increase of entropy Is the quantity obtained by dividing the increase of nonavailable energy by the temperature T, of the refrigerator.

I hope to publish a detailed treatment shortly, but in the meantime I would mention that this definition overcomes all the difficulties inherent in the conventional treatment of at least the more ordinary irreversible phenomena, such as friction, impact, gas rushing into a vacuum.

If we adopt the principle of degradation of energy as the fundamental second law of thermodynamics (as I suggested in the Boltzmann Festschrift), Clausius's statement that the entropy of the universe tends to a maximum now follows at once. So, too, do his inequalities. For every irreversible transformation in the interior of a system produces loss of available energy, and therefore (since it does not affect the total energy) increase of non-available energy, and theretore increase of entropy. We may say that entropy can be generated, but never destroyed. It follows that the total increase of entropy in the system is greater than the quantity uf entropy entering from without. This is Clausius's inquality for an irreversible non-cyclic process. If the process is velic the total gain of entropy is zero, and therefore the entropy generated in the system must be exported during the cycle. This is Clausius's inequality for a cyclic process. The introduction of the refrigerator presents no real ficulty. If non-available energy, instead of being given to the refrigerator T., is worked down reversibly to a regerator at a lower temperature T,, its amount will be de reased in the ratio T, T。. G. H. BRYAN.

The Direction of the Spiral in the Petals of

Selenipedium.

Is Selenipedium grande, S. longifolium, and S. conchiferum, the twisted petals are so arranged that the direction of the spiral is right-handed on each side.

They are not heteronymous, i.e. the right petal with a elt test and the left petal with a right twist, as in all

antelopes' horns, nor are they arranged homonymously, as in most sheep's horns,' but the twisted petals have the same direction on each side, and in the cases above mentioned the right-handed spiral is always present. In trying to find a cause for the direction, I expected it to appear that before and during the unfolding of the flower the petals were twisted when lying together, and thus took the bias, which continued during growth. If two strips of paper be laid together and twisted into a pipe-lighter, each, when separated, would exhibit the same spiral twist.

Examination of the still-folded flower proves that this simple explanation is not the true one, and, at least in S. grande, the petals are straight when they show at first (two inches or more in length), and become afterwards spirally twisted during growth and elongation.

The necessary bias to determine the direction of the spiral evidently acts after the unfolding of the flower, and is a slight force acting continuously during growth, such as would be made by the circulation if there were a difference in the circulation of the sap in the two edges of each petal. This difference would act alike in each, and would make each petal twist in the same way; but, of course, this is a mere conjectural suggestion. GEORGE WHERRY. Cambridge, October 30.

Thinking Cats.

THE story of the cat that saved the cook, in your last issue, is certainly remarkable, but surely it is not unusual for cats to find out how to direct attention when they want to get into or out of a house, or for them to conceal their kittens in curious places.

Two instances of the former occur to me among many. A cat in my father's house used to rattle the letter-plate at the front door (it was in a window near the door) whenever it was shut out, and another, in my own house, would come to any lighted window, even on the top storey, and tap at the glass if it was shut out at night. In the same house a cat hid its kittens, after one family had been destroyed, under the boards of a lead flat, so that, as they grew, it could not get them out, and directed our attention to them by running backwards and forwards. They were released by taking up the boards.

From cats to birds seems a natural transition. I have a curious instance, at this moment, of a pair of robins mistaking their own importance. Last spring they built, and reared their family, in a hole in the wall of an old country mansion, which was being rebuilt under my supervision. The wall was inside the house, in the great hall, and the female sat on her nest, looking out at the workmen, amid all the noise and disturbance of building. They disappeared in the summer, but now that the house is finished and occupied, the pair have returned, and flit about the same hall and the adjoining drawing-room, evidently under the impression that the house was built for them.

R. LANGTON COLE.

Change in the Colour of Moss Agate.

A FRIEND of mine possesses a penholder the handle of which is made of moss agate. Originally the colour of the handle was bluish throughout, but recently the upper part of the handle has become very much lighter in colour and much more transparent.

I thought perhaps some of your readers could tell me whether it is usual for moss agates to undergo changes of this kind after having been cut and polished, and, if it is usual, to what agent or agents the change is ascribed. W. A. WHITTON. County School, Bridgend, November 7.

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ON THE OCCURRENCE OF WIDMANN- stituent is, of course, ferrite, in this case nearly pure STÄTTEN'S FIGURES IN STEEL CASTINGS.

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OME little time ago, during his inspection of the metallurgical laboratories at the University College of Sheffield, Sir Norman Lockyer exhibited considerable interest in the fact then communicated to him that almost invariably small steel castings exhibited in the first stage of their manufacture the Widmannstätten figures, provided that the carbon was near the semi-saturation point of steel, namely, 0.45 per cent. The authors communicated the following brief note in the hope that it would be interesting to mineralogists and astronomers.

For many years an exhaustive research into the properties of steel castings has been proceeding at the Sheffield College. This research necessarily involves a close investigation of the influence of mass; hence the weight of the experimental castings varies from about 28 lb. to 2 tons. In such heavy castings as those last named the Widmannstätten figures are seldom found, the slow cooling of the mass exerting an influence similar to that of annealing, an operation which, as will presently be seen, causes a change in structure so profound as almost always to destroy the figures. The authors therefore selected for purposes of demonstration research casting No. 541, weighing about 30 lb. The mean analysis of drillings from this metal, taken from a portion of the casting 1 inches in diameter, registered the following figures :

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constituents, the magnification being too low to reveal its third and fourth constituents, namely, the sulphides of manganese and iron also present in minute quantities. The dark etching constituent is pearlite (21Fe+ Fe,C), its colour being due to the liberation during etching of an automatic stain composed of that dark, carbonaceous colouring matter upon which the well-known carbon colour test depends. The pale con

iron, and has obviously assumed that crystalline structure characteristic of the Widmannstätten figures. The lower half-section of Fig. 1 delineates the structure of the metal after the operation of annealing. The two stages of annealing were carried out as follows:-first, the steel, protected so far as possible

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from the air, was maintained for about seventy hours at a temperature of about 950° C.; secondly, it was allowed to cool very slowly, occupying, perhaps, another seventy hours in falling to a temperature at which it could be comfortably handled. The result was a total re-arrangement of the pattern presented by the ferrite and pearlite, and a consequent elimination of the figures. This change in structure was accompanied by a profound change also in the mechanical properties of the steel.

Fig. 2 reproduces, before and after annealing, bending tests made on bars 10 inches long and inch in diameter. The metal as cast snapped sharply after bending through an angle of 43° over a radius of

inch. The annealed steel bent through an angle of 180° without exhibiting any signs of fracture. At the request of Prof. Lewis, of Cambridge University, the authors have submitted to him duplicate sections of the steels figured in this paper. Prof. Lewis considers that an interesting point raised is as to whether the occurrence of the Widmannstätten figures in pieces of metallic iron dug out of the earth necessarily proves them to be of meteoric origin.

The authors have to thank their colleague Mr. J. H. Wreaks, demonstrator of metallography at the Sheffield College, for his patient and precise reproduction of the structures figured in this note. J. O. ARNOLD. A. MCWILLIAM,

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FORESTRY IN THE UNITED STATES. AN MONG the professional papers of the United States Geological Survey we have already noticed the first six reports dealing with the various forest reserves in the States of Oregon, Washington, and California. The two latest reports, Nos. 7 and 8, now to hand, deal with the forest conditions in the San Francisco Mountains Forest Reserve and the Black Mesa Forest Reserve in the State of Arizona. former report is by John B. Leiberg, Theodore F. Rickson, and Arthur Dodwell, with an introduction by F. G. Plummer; while the latter report was prepared by F. G. Plummer from notes by Theodore F. Rickson and Arthur Dodwell. Both forest reserves were first created by proclamation of President M'Kinley, dated August 17, 1898. The region in which the San Francisco Mountains Forest Reserve

The

is situated forms a kind of plateau, traversed by numerous deep canons and dotted by several hundred

FIG. 1.-Fire Scars on Yellow Pine.

volcanic cones, which vary in height from 100 feet to 1000 feet. The soil is various, but gravelly loam is the prevailing type. On the slopes of the volcanic cones and ridges in their neighbourhood scoriaceous soils prevail. The water-retaining capacity of the latter class of soil is not very great. The loamy soils are best adapted for forest growth. regards drainage, the visible run of permanent surface flow is small. Most of the precipitation sinks either within the reserve or in the desert or semi-desert tracks which border it.

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Electric storms do considerable damage to the standing crop in the reserves, and it is estimated that in some places as many as 5 per cent. of the trees have been struck and killed by lightning. There are twelve coniferous species in the reserve, but the yellow pine predominates, producing more than 99 per cent. of the merchantable timber, and forming go per cent. of the total forest. About the same number of broad-leaved species occur, but a complete list of them is not

available. All over the reserve the stands of yellow pine do not carry an average crop of more than 40 per cent. of the timber they are capable of producing.

This unsatisfactory condition is attributable to the numerous fires which have occurred in this region within the last 200 years. In addition, to the destruction caused by fire, careless cutting and grazing have done much damage in the reserve.

The reproductive capacity of the yellow pine in the reserve is extremely small-there being a great deficit in seedling and sapling growth. There has apparently been a complete cessation of reproduction over large areas during the past twenty or twenty-five years. This low reproductive capacity is attributed to various causes-some depending on the operation of natural agencies, others on human intervention. The grazing value of the reserve was at one time very great. As the gramineous flora of the region is a rich one, there was formerly a luxuriant growth of grass, but owing to the persistent and excessive pasturing, especially by sheep, the turf-forming grasses were reduced in size and vegetative activity, which led to various changes in the character of the subsequent vegetation. What was formerly pasture land is now covered by exuberant growths of various low desert shrubs and herbaceous Compositæ, particularly species of sunflowers.

The agricultural value of the region is not great, there being only some 2500 acres under the plough, and these occur in the now dry beds of what were formerly Stone-man and Mormon lakes, or at the foot of ridges where local areas of seepage exist. The crops consist of oats, wheat, and potatoes. There is no fruit culture in this region. This reserve, like the others, is subdivided into townships and ranges, the detailed descriptions of which are included in the report. At the end we have a very useful summary, showing in tabular form a classification of lands in the reserve by townships. The maps and photographic illustrations are of the same high standard as those which accompany the other reports of this series.

The Black Mesa Forest Reserve comprises an area of 2786 square miles, made up as follows:

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Square miles. 2248'5 391 140

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FIG. 2.-Large Growth of Alligator Juniper.

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A very striking feature of the report is the decrease in the water supply due to successive seasons of drought, which have practically destroyed the value

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of the grazing and agricultural areas in the reserve. Three years ago the wheat crop yielded 5000 bushels. The following year it fell to 2500 bushels, and last season the yield was only 800 bushels. A cattle ranche in the range, which used to graze more than 100,000 head, will now support not more than 9000 head. a remedy it is suggested to adopt stringent rules, regulating the number of stock and the areas on which they shall be grazed on each permit. Very little lumbering has been carried out within the reserve, which is apparently due to the difficulties and expense of transport. The timber species, coniferous and broad-leaved, number fifteen, the yellow pine being the principal timber tree. It is distributed uniformly throughout the extent of the reserve. In some ranges it forms a pure forest. Its average height is 125 feet, with 24 feet of clear trunk with a diameter of 18 inches at breast height. It varies in age from 125 to 150

years.

The Engelmann's spruce occupies the moister areas above an altitude of 9000 feet. It averages 70 feet in height and 10 inches in diameter. Its age varies from 50 to 75 years. Its growth is extremely rapid, but the tree is usually clothed with branches to the ground. A variety of the Engelmann's spruce, Picea engelmannii, var. Franciscana, known as the Arizona spruce, gives much better results, averaging 100 feet in height with 20 feet of clear trunk and a diameter of 18 inches. Red fir, white fir, western white pine, alligator juniper, and Arizona cypress also occur within the area. The deciduous trees are confined to the borders of streams and marshy areas. The reproductive capacity of the various species is exceptionally good, especially where the young growth is afforded shelter by the larger trees. The underbrush throughout the areas in which the yellow pine predominates is very small, and consequently this region has not suffered much injury from forest fires. The report also embodies detailed descriptions of the various subdivisions of the range, together with carefully prepared maps and beautiful photographic plates. Of the latter we have reproduced two as an example of the interesting way in which these papers are illustrated.

TECHNICAL EDUCATION IN LONDON.1

THE

HE last report of the Technical Education Board of the London County Council, dealing with the year 1903-4, directs special attention to the progress made in the provision of technical, secondary, and higher education in London during the past eleven years. Under the recent Education Act (London), 1903, the administration of the whole of the education of London passed into the hands of the new Education Committee, and the Technical Education Board ceased to exist. The present report is consequently opportune, and serves to record the great services which have been rendered to education in London by the late Board.

The most striking features of the report are the evidences provided of the increase and rapid development of polytechnic institutions, the establishment and success of London County Council schools and technical institutes, and the improvement in the equipment and staffing of secondary schools. The extent of the advances made can be estimated satisfactorily by comparing the number of educational institutions providing good scientific and technical education at the time of the supersession of the Technical Board with the number in existence in 1893, when Mr. Llewellyn Smith reported on the provision made for technical

1 "Annual Report of the Technical Education Board of the London County Council, 1903-1904. (Westminster: P. S. King and Son, 1904.) Price 2s. 6d.

instruction at that time. To take the case of the laboratory accommodation for the teaching of chemistry. In 1893 there appear to have been about fourteen chemical laboratories in London open in the evening for instruction; since that time well equipped departments for teaching practical chemistry have been opened in eleven new polytechnic institutions. The total volume of instruction in evening classes in chemistry in 1893 was only about 38,000 student-hours per session, and in polytechnics under 15,000 studenthours. In 1893, after omitting the attendances of students who did not attend for more than twenty hours during the session, the amount of time devoted to evening work in theoretical and practical chemistry amounted to 64,554 student-hours in the polytechnics alone.

The result obtained by comparing the advance made in the teaching of electricity and electrical technology is just as striking as in the case of chemistry. In 1893 there were five electrical laboratories open for evening instruction, while in 1903 there were twenty-three institutions giving evening instruction in electricity or electrical technology, or both. In practical electrical engineering there were only four centres in 1893 available for evening instruction, and only one applied for aid from the Board, and at this institution there were thirty-eight students. During the session 1902-3 there were, in polytechnics aided by the Board, a large and increasing number of students for electrical engineering, and the volume of instruction, omitting students who attended for less than twenty hours during the session, amounted to 43,909 student-hours. In addition to these, a large number attended classes in electricity and magnetism in the physics departments of the institutions. The volume of instruction here reached 32,872 student-hours.

Ten years ago there was scarcely any provision in London for pure technological teaching. From the list of evening classes for 1903 it appears that technological instruction is now available in a great variety of subjects, of which the most important are:-bricklaying and brick-cutting in twelve institutions, cabinetmaking in nine, carpentry and joinery in twenty, furniture design in nine, masonry in nine, metal-plate work in eight, painting and decorating in twelve, photoprocess work in four, plastering in nine, plumbing in fifteen, printing in four, smithing in six, tailors' cutting in seven, and upholstery in six. This rapid increase in the number of polytechnics and technical institutes in which adequate provision is made for practical instruction in trade subjects has had a remarkable effect in producing an interest in the scientific principles underlying the various trades concerned. As an example, the report quotes the case of the Northampton Institute in Clerkenwell, in which district there is a very large number of special trades. order to meet the demands of the neighbourhood, classes were started in subjects in which no organised technical instruction had previously been given in London. Some of these have been remarkably successful, and in several cases it has been found necessary to increase the number of evenings of instruction in order to provide for the large number of students in attendance.

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There has been also, says the report, a natural tendency during the past few years for sporadic classes in trade subjects to disappear in consequence of the increasing popularity of the polytechnics and larger technical institutes, in which are found thoroughly well equipped laboratories and workshops. The number of distinct trades in which practical instruction is provided, and also the number of centres where such courses of instruction can be obtained, have more than doubled during the past nine years,

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