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THURSDAY, JANUARY 1, 1874

THE YORKSHIRE COLLEGE OF SCIENCE

"VT OW that a scheme for a College of Science at Leeds has been all but completed, under the chairmanship of Lord F. C. Cavendish, M.P., it seems somewhat surprising that such an institution in connection with Yorkshire has not been thought of long ere now. It is the largest county in England, carries on a greater variety of industries all more or less dependent for success on the results of scientific research, and boasts of a larger number of local scientific societies and field-clubs than any other county in the three kingdoms, as we have shown in our articles on that subject. However, "better late than never;" and to judge from the prospectus and subscription lists, a very fair start is likely to be made. The scheme proposed by the committee formed at Leeds in 1869 involved an expenditure of 100,000/., but it is not intended at present to carry out the whole of this scheme, but to commence on a smaller scale in temporary premises and with a limited number of professors. We have no doubt, from the hearty way in which the proposal has so far been met, that the college will be a success, and that ere long it will be possessed of a handsome building of its own, with a full staff of professors.

From what follows, it will be seen that the teaching will have a practical or technical aspect, having regard to the processes connected with the multifarious arts and manufactures which occupy the large population of Yorkshire. In the midst of an eminently practical people, there can be no fear of this consideration being neglected, but we hope that in the long run the claims of pure science will not be overlooked, for it is every day being more and more clearly proved that a preliminary training in pure scientific research is the best introduction to a "technical" education; and very many of the industrial applications of science have been found out by students who took no thought of the practical issues of their investigations. There is more than one institution in America which might, in this respect, be taken as models for a technical college.

The Yorkshire College of Science, the Prospectus tells us, is intended to supply an urgent and recognised want, viz.:—Instruction in those Sciences which are applicable to the Industrial Arts, particularly in their relation to Manufactures, Engineering, Mining, and Agriculture. It is designed for the use of persons who will afterwards be engaged in those callings as foremen, managers, or employers; and also for the training of teachers for ordinary Science Schools and Classes.

To carry out the object of the College, it is proposed to establish Professorships in (1) Chemistry and its application to Metallurgy, Manufactures, and Agriculture; (2) Civil and Mechanical Engineering; (3) Physics and Mathematics; (4) Geology and Mining.

The Provisional Committee seem to have right notions as to how scientific men ought to be treated. To obtain the services of eminent scientific men, they say, the payment to each Professor cannot be less than 300/. per annum, in addition to a proportion of the students' fees. A precarious income, if raised by annual subscriptions, Vol. Ix.—No. 218

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, sundry annual expenses for working and maintenance will be required, and these will be paid out of the general fund. The Committee therefore appeal for contributions upon a generous scale commensurate with the importance of the proposed scheme. This appeal has been well answered already ; but we hope that the Committee will not rest until the whole of the original scheme has been realised.

The Committee refer to the sum raised for the Newcastle College of Science, 22,025/., with an annual contribution of 1,000/. from the University of Durham, and say with justice, that, considering that the wealth of the district over which the benefits conferred by the Yorkshire College of Science will extend is at least equal to the Newcastle district, it is to be hoped that the public. spirit of Yorkshiremen in behalf of the College will be as freely expressed.

To the Owens College, Manchester, the sum of 13,500/. has been contributed by the engineering profession towards the endowment of the chair for Engineering; and the hope is entertained that towards the endowment of the Professorship in that subject in the Yorkshire College of Science, aid may be forthcoming from a similar source. The chair for Chemistry has also peculiar claims for support upon the manufacturers of the county whose business requires the aid of chemical science.

Arrangements will be made for the establishment of scholarships at the College. All donors of 500/. and upwards towards the College funds will be entitled to nominate to a free studentship for a term of years.

It is proposed to vest the government of the College in a board of governors, consisting of (a) all subscribers of 250/. and upwards; (6) fifty governors elected by the general body of subscribers; (c) two professors elected by the professorial staff. The governors shall hold two meetings in the year, shall appoint trustees, shall audit the accounts, shall receive the annual report from the council of the College, and shall constitute a court of appeal in certain cases. The ordinary administration shall be in the hands of a body called the council This shall consist of fifteen members, including a chairman, to be elected out of and by the governors.

One of our wealthy City Companies, the Clothworkers' Company, we are glad to see, has generously come forward in the interests of the College as well as in the interests of the particular branch of manufacture with which the Company is connected, by endowing a Professorship of Textile Fabrics with 300/. a year. The subscription of the coal-owners alone amounts to some thousands of pounds, and we have no doubt, when the time comes to extend the sphere of the College and to give it a permanent building of its own, this wealthy class will see it to be their duty largely to add to this subscription. We hope also that others of our City Companies will see it to be their interest to lend a helping hand to the young institution. There are several such technical institutions on the Continent, and it is on this account that in several respects Continental manufactures are much superior to those of Britain. Let us hope that this may not be much longer the case, but that by the establishment of the Yorkshire

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College of Science, and similar institutions in other districts, all who are in any way connected with our arts and manufactures may be trained to work on a method so really scientific that Britain shall in this, as she certainly is in some other respects, be foremost among the nations.

REFRACTION OF LIGHT MECHANICALLY ILLUSTRATED

IN preparing an elementary lecture on Light, intended to be given at the Taunton College School, I have had to consider how best to explain the somewhat abstruse principle of optical refraction. It is true that Sir John 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 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 imagine a line of soldiers marching across a tract of country divided at a straight boundary into two regions, the one level ground suited for marching, the other rough and difficult to walk over. Now if the line of soldiers march with their line of front oblique to the boundary, the men on the side just engaged in the heavy ground

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will be retarded as soon as they cross into it, so that if the line be kept unbroken, the consequence must be a change of front, which will leave the whole body of men marching across the heavy ground in a new direction— in a word, their direction of march will have been refracted. Now the light-waves emitted from a radiant 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 the learner, to whom refraction thenceforth ceases to be a molecular mystery, and becomes an intelligible mechanical act dependent on the resistance of the two media and the form of their limiting surface. Probably no point in all Herschel's lectures has fixed itself in the memory of so many intelligent readers.

In following up the train of thought started by Sir John Herschel's comparison, it occurred to me that an instrument made to perform refraction mechanically would be useful in teaching optics, and that such a contrivance would only require a pair of wheels running on a table, into and out of a resisting medium. After a

number of trials, made with the help of Mr. R. Knight, a simple arrangement has been completed, which answers satisfactorily in showing the behaviour of a ray of light under the various circumstances of ordinary refraction. Pieces of a thick-piled velvety plush known as " imitation 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 boxwood wheels mounted loosely on a stout iron axle, and is trundled across the board, or still better, the board itself

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is tilted up, and the runner let go in the proper starting direction. The following figures show the path of the wheels, always from right to left of the page.

In Fig. 1, the runner starting from A, enters the rectangle of velvet at B, where its left wheel being first retarded, it shifts round into the direction BC, till it reaches 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 resistance, would make it emerge near F, at a small angle

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to the side. But the left wheel passing on to the smooth surface gains so much on the right wheel still in the velvet, that the axle slews round, the left wheel re-enters th velvet, and the runner goes off in the direction FG, thus illustrating the total reflexion which takes place when a ray of light is directed to emerge very obliquely from a more into a less resisting medium, as from a glass prism or a surface of water into air.

The action of the double-convex lens in causing parallel or divergent rays to converge is shown by the path of the runner in Fig. 3, which requires no further explanation, nor does that corresponding to the divergent action of the double-concave lens, Fig. 4. By starting two runners at once from the right-hand side of the board, so as to traverse the upper and lower parts of the convex lens, they are made to run into one another, thus illustrating the meeting of rays in a focus.

Lastly, by using two runners with wheels of different diameters, as the refraction depends on the resistance to the wheels by the velvet, the apparatus may be so inclined as to show plainly their consequent difference of refractive angles. The courses of the two arc seen in Fig. 5. This experiment, however, requires some nicety of arrangement

Now the separation of rays of different refrangibilities by a prism being due to a like cause, this experiment serves to illustrate mechanically the decomposition of white light. Let the large-wheeled runner represent the red ray, and the small-wheeled runner the violet ray, the principle of the prismatic spectrum becomes at once evident.

For the information of any who may wish to reproduce this simple apparatus, I may state the dimensions I have found convenient. The wheels may be 1J in. and 2 in., with rounded edges, mounted on a nearly half-inch iron axle, turned down to | in. at the ends. The boards may be 2 ft 6 in. by I ft. 6 in., with velvet on each side. It is conve. nient to place the velvet nearer to one end of the board to leave room at the other for starting the runner; and care must be taken to cut the velvet so as to present a good resisting surface, as this varies with the direction of the pile. In using the apparatus for teaching, care in manipulation is required to neutralise the defects of the texture. Some kinds of" Utrecht velvet," to be had from the upholsterers, are more uniform than the "imitation seal-skin," and thus work more equally, but their effect is not so striking. Wet sand will answer equally well with the velvet, if metal wheels be used.

Edward B. Tylor

THE FRESHWATER FISH OF INDIA AND BUR MA H

Report on the Freshwater Fish and Fisheries of India and Burmah. By Surgeon-Major Francis Day, F.L.S. and F.Z.S., Inspector-General of Fisheries in India. 8vo. (Calcutta, 1873.)

IN the introductory part the author states that the present report is the result of investigations commenced by him in the year 1868, into whether a wasteful destruction of the freshwater fisheries is or is not occurring in India and Burmah. He comes to the conclusion that a wasteful destruction of fish is going on to a very great extent, that these fisheries are more and more deteriorating, and that immediate legislation is called for, to prevent the entire failure of a most important article of food.

The steps taken by the Inspector-General to ascertain the facts on which he bases his report were twofold. He personally inspected districts of various parts of the Indian Empire, and supplemented his own observations by collecting the opinions of European and Native officials, to whom he addressed a series of questions bearing upon the subject. Accordingly the book before us is divided into two parts :—(1) The report proper, pp. 1-118; and (2) A resume" of the answers returned, with marginal

notes by the reporter, pp. i.-cexxxvi. An article on "Fish as Food, or the reputed Origin of Disease," an Enumeration of the Indian freshwater fishes, and Notes on preserving specimens of fish, conclude the volume.

Europeans who have formed favourable ideas respecting Indian rivers and their abundance of fishes from the accounts which so frequently enliven the sporting papers of the day, will find them rudely dispelled by this report. It is true that not a few of the resident officials deny the decrease of fishes, and deprecate legislative interference altogether. Thus, for instance, the Commissioner of the Agra Division writes that there is no reason to apprehend that any wholesale destruction of fish goes on in these parts. A close-time might no doubt be introduced by law for the protection of fish during the breeding season, but it does not appear to him that it would be easy to carry out such a measure, or that there is any compensating object to be gained ; that "it is a useful maxim— de minimis non curat lex—minute legislation is unbefitting our position in this country, and more likely to expose our Government to ridicule than to any results of important benefits to the people;" "it is in the highest degree undesirable that the public mind should be disturbed by gratuitous interference on the part of an alien administration, enforced by not very trustworthy agency." On the other hand, the Inspector adduces such incontrovertible evidence in favour of the conclusion he has arrived at, that we can but agree with him that in numerous districts the freshwater fisheries are in danger of being utterly destroyed, and this must appear to call for speedy interference by the Government all the more, as those districts are among the most populous, in which this article of food can be least spared.

Naturally one looks first for the causes by which the Indian fisheries are said to have been thus reduced; and 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 former rule, fisheries formed royalties mostly let out to contractors, who alone in the district possessed the right to sell fish, and that they permitted the people, on payment, to capture fish for their own consumption ; that the men who followed the occupation of fishing formed distinct crafts or castes, exercising their calling with certain restrictions and regulations. Under British rule the renting system was abolished; with the most philanthropic intentions, the British gave to the people liberty to fish when and where they pleased ; where everybody could fish, fishing ceased to be a distinct calling; breedingfish were captured without regard to season; and when the supply of larger fish commenced to fail, it became the practice to catch undersized fish and fry. Add to this, that a number of irrigation weirs and dams were erected, preventing the fish from resorting to suitable spawning-beds, that fixed engines for the capture of fish are now used, where previously they were never permitted, and the natural result is the lamentable state as represented by the Inspector.

We need not enter at present into the remedial measures provisionally proposed by Mr. Day. His proposals, as well as the opinions of his opponents, will no doubt find due consideration on the part of the Indian Government. But I will not conclude this notice, without alluding to one or two of the reports of European officials, which will show that, however weighty their evidence may be as regards the practical side of the question, their opinions in scientific matters are open to criticism. Mr. Day had drawn attention to the destruction of fish by various kinds of crocodiles, very properly recommending that rewards should be paid for their eggs. To this one of the officials replies :—" Waging war against such fishdestroying animals as crocodiles appears to me absurd. I have no doubt at all but that a general destruction of crocodiles would directly frustrate the end hoped for by their destruction. Their very presence in numbers, it being given that they live on fish, shows that the supply of fish is abundant, which is all that anyone requires, and nature in these matters, if left alone, keeps the balance even, and resents interference." This is exactly the same view as that held by the modem advocates of a general preservation of birds, who would preserve even such as the sparrow-hawk and cormorant, and who forget that nature itself, in distributing animal life, does not always consult the convenience of man. In India, the presence of tigers, poisonous snakes and crocodiles, would appear to prevent this doctrine from being generally adopted by the European community. Another official refers to a "very exhaustive and carefully drawn up report" from a Civil Surgeon in his district; this report is accompanied by a list of the freshwater fishes, in which occur some species with Buchanan-Hamilton designations, others with Latin terms derived from a dictionary, a cod-fish, a john dory, and " a very common fish, the scientific name of which is supposed to be Lacerta scincus /" Can anyone doubt after this that a comprehensive and well-illustrated hand-book of Indian Freshwater Fishes with an introduce tory treatise on the elements of Ichthyology is called for?

Albert Gunther

KOHLRAUSCH'S "PHYSICAL MEASUREMENTS"

An Introduction to Physical Measurements, with Appendices on Absolute Electrical Measurement, &c. By Dr. F. Kohlrausch. Translated from the Second German Edition by T. H. Waller, B.A., B.Sc, and H. R. Procter, F.C.S. (London: J. and A. Churchill, New Burlington Street, 1873.)

MESSRS. T. H. WALLER and H. R. Procter have furnished us with a translation of the second edition of Dr. KoVrausch's " Physical Measurements," to which they have aided several useful Appendices and Tables.

Their work is intended to serve as a text-book for students in experiment :1 physics, and consists mainly of a collection of the formulae used in correcting and applying the results of the simpler experiments in weighing and measuring, heat, light, electricity, and magnetism, accompanied in each case by such an account of the method of observation employed as may suffice to render them intelligible.

The limits which the author assigned to himself are very clearly laid down in the Translators' preface, in which we are informed that "descriptions of apparatus are but rarely given, as students mostly have instruments provided for them," and also that "the mathematical knowledge

required is but very elementary, as the proofs of the formulae are only given when they present no complex arguments," but it should perhaps have been added that, even in cases where the apparatus is simple, outlines of the mode of performing an experiment are generally alone supplied, the teacher being left to explain to his pupils the niceties of arrangement and manipulation.

Regarded as a syllabus of a course of physics, the book is incomplete, no account, for instance, being given of Favre and Silberman's Calorimeter, or, with the exception of saccharimetry, of experiments on polarised light; and if the author's plan be thought to justify the exclusion of these, the same reason can hardly account for the omission of methods for determining melting points, or the specific gravity of substances whose constitution is altered by exposure to the atmosphere, or the ratio of the intensities of the illuminations produced by two sources of light, or of all experiments relating to the capillary elevation of liquids in fine tubes.

It is, however, as a collection of formulae that " Physical Measurements" is likely to prove most useful, and from this point of view the "Introduction" seems to us one of the best parts of the book. It contains the rules for finding the mean and probable errors of a set of observations, and for determining empirical constants by the method of least squares, together with hints as to how to shorten the labour often wasted in the calculation of corrections ; points on which a short practical treatise like that here provided will afford great assistance to those who are not mathematicians.

The sections devoted to weighing and measuring are full and good, especially those which relate to the use of the balance, but heat and light are not treated of in an equally satisfactory manner.

The experiments on these subjects which are described are not numerous enough to satisfy the requirements of large laboratories. Moreover, sufficient attention seems scarcely to have been paid to the fact that students should be encouraged to apply corrections to the results of experiments which they perform, not so much on account of the more accurate numerical values thereby obtained, as for the sake of the excellent practice the necessary observations often afford, and the insight gained into the theoretical principles on which they are founded. A case in j point is the omission in the article on the Determination of Specific Heats by the Method of Mixtures of any account of the correction employed by Regnault for the loss of heat by radiation.

We miss all mention of the optical bank, and the mathematical expressions for results involving the determination of distance in terms of differential measures on that instrument. In the article on the spherometer, which is in other respects incomplete, we see no instructions for finding the radius of a spherical surface too small to permit the instrument to be placed upon it ; and omissions are made in the pages devoted to the spectrometer, the goniometer, and elsewhere, which combine to render the section on Light very imperfect.

Nearly one half of the book is given up to Electricity and Magnetism, subjects in the study of which assistance can be more readily rendered by the method of treatment here adopted than in those we have been discussing, as numerous mathematical formulas are required which are in many cases obtained by calculations beyond the grasp of the less advanced pupils"; and the Translators have considerably improved what was already good by several Appendices, among which one of the most important is that on Thomson's electrometer. Some preliminary sections are devoted to the reduction of observations made with the miiror and scale to angular measure, to the determination of the position of equilibrium and time of oscillation of a magnetic needle and similar topics, while the methods of reading the various magnetometers and galvanometers, and the measurement of resistance and electromotive force, are afterwards discussed.

On the whole the principal fault we have to find with the book is a want of fulness, especially in the earlier portions. 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 Science increases, and we are not aware of the existence of any manual which gives the information contained in it in an equally compact and handy form ; while the tables, thirty in number, which fill the concluding pages, will often save time and trouble to those engaged in laboratory work. Although, then, as we have already pointed out, we consider it capable of very considerable improvement, yet probably most teachers of Experimental Physics will obtain some useful hints from its perusal, even if they do not adopt it as a text-book for their pupils. A. R.

OUR BOOK SHELF

Pheasants for Coverts and Aviaries. By W. B. Tegetmeier, F.Z.S. (London :*Horace Cox. 1873.)

Any work on animals which appeals to so many different human weaknesses as the Pheasants, must be popular if the least effort has been made to do the subject justice. The one before us has merits which make it peculiarly acceptable. It is by the hand of an author who has devoted his life to the careful study of the natures and habits of the Gallinaceous birds and Pigeons, and who has long since made himself well known by wonts on some of the genera, which have become the standard literature of the points on which they treat. In the handsome volume before us Mr. J. W. Wood's excellent and truthful illustrations add greatly to its value, though the absence of coloration has made it more than difficult in some cases to produce an approach to the gorgeous appearance of some of the species depicted. Among those that suffer most from this deficiency, are the Japanese Pheasant {Phasianus versicolor), whose chief beauty consists in the richness and delicacy of the shades of its plumage, and the Golden Pheasant (Thaumelia picla), with its ally, the Amherst Pheasant (T. amherstia), whose resplendent hues even the best artist finds it difficult to represent. The Reeves' Pheasant (P. reevesii), and the Eared Pheasant {Crossoptilon mantchuricutn), however, form excellent and most truthful pictures, colours in them not being such important features. Mr. Tegetmeier, besides describing each of those species which are the love of the sportsman and the pride of the aviary, devoti s the earlier part of his work to the discussion of points of great practical interest. After a short history of the Pheasants as a family, from which it is clear that they were introduced into this country from Asia Minor, the native home of the common Pheasant {P. colchicus), as early as the reign of King Harold, and probably by the Romans, a series of chapters is given on the management of the bird in preserves and in confinement, together with

an account of the diseases to which it is most liable. These are replete with practical detail that must be most valuable to the many who spend such large sums on preserving game, and to those who have the actual superintendence of the coverts themselves. Particular attention is drawn to the great difference between birds, like the common Fowl (Gallus bankiva), which are capable of domestication in the true sense of the word, and the Pheasants, which, though individuals are frequently known to become tame, can never be really domesticated ; even the young ones taking to the woods on the earliest opportunity, whilst the opposite inherent peculiarities of the poultry have given rise to the proverb— "Curses, like chickens, come home to roost." Altogether this work supplies a long-felt want, and its perusal will well repay anyone who takes it up.

LETTERS TO THE EDITOR

[The Editor does not hold himself responsible for opinions expressed by his correspondents. No notice is taken of anonymous communications. ]

Wasps

PERHArs it may be of interest to some of your readers, who make entomology their study, to know that the wasps in a nest about a mile from this were still tolerably active on the 13th of this month, when my attention was attracted by the loud buzzing of three or four wasps at the entrance, apparently ventilating it with their wings after the manner of bees. I again visited the lace on the 23rd. There were at first no signs of life outside; ut stamping on the ground above caused a considerable number 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 260 in October, 25°.in November, and 29° on the 10th and nth of December, and the 13th having been mild, and so also the 23rd) and the bad conducting power of the nearly cut out peat bog in which the nest was situated.

Birr Castle, Farsonstown, Dec. 24, 1873 RossK

The Potato Disease and Lord Cathcart's Prize

No one acquainted with botanists and botanical science can feel surprised at the decision of the committee in this matter, and it must be confessed that, however well meant, the offer of the loo/, prize was a great mistake which has only ended in producing ninety-four unsatisfactory essays and the loss of a year.

Little else could have been expected, for the Council of the Royal Agricultural Society must surely be aware that the men (in this country at least) who are competent to write anything nau on the subject could certainly be counted in units, and these men could not enter into the competition for more reasons than one, not the least being the loss of status such a proceeding would entail.

It appears to me that the committee have even now hardly hit the right nail upon the head in recommending a grant of money to "some competent mycologist" to investigate the life history of the fungus during a certain period of its life. If the investigation is carried on by any one man it is sure to end in failure. It would be far belter lor the committee to recommend that five or six competent botanists should each write an essay on the subject from his own point of view, each essay to be published in the Society's journal. There are many reasons why ibis would be best. I will give one. Payen has figured and described certain ciliated bodies found in spent potatoes, and which Berkeley and other botanists have looked upon as the probable resting-spores of the J'tronospora. Montague has referred these same bodies to the Sepcdonici, whilst I am by no means sure that the objtcs do not belong to the Siilbacci, and are no other than Volutella citiata. However this may be, I have met with the last in spent potati.es in immediate connection with thePeronospora itself. Where competent observers differ in opinion it is better to get the views of all. It would be very unwise to restrict the observations to any particular period of the growth of the plant, and very little would be added to our knowledge were the resting spores themselves found; tor, resting spores or no resting spores, it is an ascertained fact that the living

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