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of "hundreds of motor-cars crashing through the
Messrs. W. HEFFER AND SONS, LTD., Cambridge, trees.” The storm occurred at about 4 p.m. in Devon, at 5.40 to 5.50 p.m. in South Wales, at 7.35 to 7.45
have just issued a classified catalogue of numerous p.m. in Shropshire, and at 9 p.m. in Cheshire. The
scientific books, periodicals, and publications of scien
tific societies which they offer for sale, including large progress of the central area of the storm is given as
selections from the libraries of the late Sir Robert Ball 36 miles an hour No absolute measurement of wind
and Dr. J. Reynolds Green. The catalogue contains velocity was secured, and a similar absence of baro
titles and descriptions of many rare and valuable meter records is mentioned, with the exception of one station only a few yards from the South Wales track,
works which may be purchased at reasonable prices where the record shows a fall of pressure from
for private or public libraries. 29.20 in. to 28.91 in., followed by an almost immediate rise.
OUR ASTRONOMICAL COLUMN. The Scientific American for February 13 contains
Comet Notes.- In the Astronomische Nachrichten the third of the series of articles entitled “Doing
(No. 4789) Dr. Elis Strömgren communicates
ephemeris up to March 29 for comet Mellish (1915a), without Europe," to which we referred in these
computed by Herren J. Braae and J. Fisher-Petersen, columns a month ago. The principal object of the from the parabolic elements given by the latter, with articles is to show how vast are the mineral resources Herr R. Andersen. The data for the present week are of the country and how little they are utilised. The as follows:
Dec. (true) Mag. present article deals mainly with the barium salts used in the manufacture of paint. Up to the commence
17 55 53
-o 34:9 8.8 ment of the present war these had been imported
18 from Germany, but one of the largest paint manu
18 facturers of New York has commenced manufacturing
18 5 9
8-5 them from an ore found in Tennessee, and now turns out 15 tons a day. In respect to potash salts, of
The comet lies approximately between y Ophiuchi which the annual import from Germany exceeded
and n Serpentis. 3,000,000l., the United States Government has directed
Herr K. Hillebrand, in an Ephemeris Circular of the
Astronomische Nachrichten (No. 478), publishes the attention to the natural deposit of the salts at Searles
elements and ephemeris of the periodic comet of WinLake, California, and a manufacturing plant has been necke for its appearance in the current year. The set up there the success or failure of which will be latter extends from April 16 to the end of August. watched with interest. Soda, magnesia, and several A search ephemeris for Tempel's comet (Ephemeris other substances are also mentioned as being found in Circular, No. 479) is given by Herr J. Braae. * In 1910 abundance in the country, and as only requiring work
this comet was not seen, but it is pointed out that
this year it will be a little more favourable for observaing to supply all requirements.
tion. The ephemeris is extended to the end of June
of the present year, and will be continued later. An interesting paper on the internal-combustion engine in the oil field was read at the Institution of
The STRUCTURE OF THE Hy LINE IN STELLAR SPECTRA. Petroleum Technologists on March 18 by Mr. F. G.
- In this column for July 31 of last year attention was
directed to a paper by Herr K. F. Bottlinger, in which Rappoport. It appears that the steam engine still
was shown the result of a study of the intensity dislargely holds its own despite its inefficiency, the reason tribution of lines in many of the brighter stars. In a for this being in the special character of the work recent number of the Astronomische Nachrichten to be done in boring and baling oil wells. Great (No. 4788, vol. cc., No. 12) Dr. Adolf Hnatek gives flexibility in power and speed is required, and while his conclusions from rather a similar investigation.
The author has measured both the intensity (Linienelectric power distributed from central stations is ideal
tiefe) and breadth (Linienbreite) of the Hy line in from other points of view, electricity lacks that flexi
several bright stars, and summarises the values debility at the well which makes steam power so con- duced according to the spectral types of the stars venient. The oil .engine has created a large and examined. Thus, in the case of the line-width the important sphere of its own by facilitating profitable following are mean values in Angström units which
he has deduced. operation of a large class of wells having a small yield. Such wells had formerly to be closed, and the Maury
16 advent of the oil engine with its low fuel-consumption
1'40 has rendered possible their operation. The oil engine
0.81 is well adapted for outlying districts and for prospect- XIII-XV
0-35 ing work; the Binagadi oil field, without adequate
Summarising the values of the line-intensity (Linienwater supply, is worked almost entirely by means
tiefe), he points out that they show also a similar of oil engines. The new Ural and Biellik districts relation to the spectral types; these intensity values in Russia are largely worked by oil engines. Appli- are added in the last column of the above table. The cations of the gas engine are also discussed, and paper contains also a number of curves of the Hy lines reference is made to an engine made by Messrs.
in the individual stars arranged in groups according Tangye, which can be run as a gas engine, or as an
to their spectral classes. While the above investiga
tion deals only with one line and a small number of oil engine, by alteration of certain parts. Several of
stars, the author hopes to extend the research to more these engines are in successful operation on the Baku lines and stars in order to deduce results of a more oil field.
definite and trustworthy value.
THE HARVARD COLLEGE OBSERVATORY REPORT.-The tions near the Atlantic are characterised mainly by annual report of the director of the Astronomical Ob- brachypleionian variations. servatory of Harvard College for the year ending In an earlier paper Mr. Arctowski dealt with the September 30, 1914, indicates the completion of a large period 1891-1900, and he takes the mean values for amount of work in both observation and publication. this period as normals, and plots on maps the differ. Prof. E. C. Pickering refers in the first place to the ence from normal of the values during each year of principal work of the observatory, namely, its publica- the decade 1900-09. The areas where the differences tions and the importance of issuing these as soon as are positive he cails thermopleions, and the areas of possible to prevent loss by fire. Thus observations negative differences antipleions. He finds that certain from 1892–1912 with the 15-in. equatorial, from 1888-98 years, in particular 1900, 1908, are characterised by with the 8-in. transit circle, and from 1898-1912 with thermopleionian areas, while others, such as 1904, the 12-in. meridian photometer are now printed, and 1907, are years of antipleions. The most important the discussions are in progress. The director directs cause of these differences is the variation of solar attention to the improvement in photographic processes radiation, but there are also supplementary causes resulting in the replacement of practically all visual such as the presence of volcanic dust in large quanwork. The report then describes in more detail the tities, or exceptional ice conditions in the polar work of the Henry Draper Memorial, the principal regions. research of which is the New Draper Catalogue; last Many of the maps which illustrate the results of the year Miss Cannon classified 60,386 spectra, making a investigation are on a very small scale; the course of total of 160,541. The activities of the Boyden depart- the thermopleions and thermomeions is obscured by ment, the Bruce photographic telescope, and the Blue the attempt to show relatively microscopical geographHill Meteorology Observatory are briefly summarised, ical details. while among the many items mentioned under the Mr. Arctowski finds it astonishing that after all the heading “Miscellaneous " the work of Prof. W. H. efforts which are made to organise and maintain Pickering at the Mandeville Station, in Jamaica, is meteorological stations all over the world, the actual described, much time having been devoted to the study results of the work are so inaccessible. Even for the of the planet Mars during its recent opposition. area with which he dealt he could only get much of
STAR CHARTS FOR METEOR OBSERVERS.-One of the the data by writing personally to the directors of the contributions to the January number of the Journal different meteorological institutes. This is a defect of the Royal Astronomical Society of Canada (vol. ix.,
which will be remedied when meteorologists of No. 1, p. 7) is entitled “A Gnomonic Star Atlas," and
different countries undertake to contribute to a central contains a set of thirteen maps, prepared by Mr. Rey- bureau representative regional values based on a selecnold K. Young, intended to facilitate the observa. tion of stations which can only be chosen satisfactorily tion of meteors and the plotting of their paths. The
by the local organisation. method of the projection of the map is such that
There is another defect which is almost more great circles in the sky are equivalent to straight
serious, viz., the lack of continuity in the records for lines on the map, thus making the plotting of the
individual stations due to changes of situation or meteor trails more easy. The maps are devoid of instruments. For example, Mr. Arctowski finds that unnecessary detail. The positions of the stars are
the difference of temperature between Chicago and given for the epoch 1900 correct to within one-tenth of
Milwaukee was nearly 4° F. in the decade 1873-82, à degree, and all stars down to 5th magnitude and
while in the decade 1896-1909 the difference was only the brighter variables are included. A good margin
2° F. The change is almost certainly due to change of overlap has been allowed in each map, which
of instrument or site, and as it is of the same order should prove very useful.
of magnitude as the changes with which he deals, it indicates the need for great caution.
The difficulty of securing comparable continuous FLUCTUATIONS OF TEMPERATURE IN
records is indeed one of the most serious problems
with which organised meteorology has to deal. EUROPE AND AMERICA. R. H. ARCTOWSKI, in a paper published in
vol. xxiv. of the Annals of the New York Academy of Sciences, considers the problem of varia- REFINING GOLD BY ELECTROLYSIS. tion of temperature over the whole earth. After a brief statement of the general problem and the THE problem presented by the necessity of refining methods by which it may be attacked, he explains
gold was one for which a solution was sought that he could not deal single-handed with the arrange
at least as early as the time, about 1.c. 700, when
coins were first manufactured in the Western world. ment and discussion of the actual values even over the whole of the northern hemisphere, and confines
Apart from toughening or the removal of base metals, himself to the detailed survey of the variations over
which was sufficiently cared for by the ancient pro
cess of cupellation, it is clear that some measure of North America and Europe. He also compares the
success attended the efforts made to part gold and results with one or two representative equatorial and
silver. Thus, some of the ancient Greek coins consouthern hemisphere stations. From a study of the
taining 997 or 998 per 1000 of gold. The earliest values at one of these, Arequipa, in Peru, he deduces
parting process used was one of cementation, which that the temperature changes are partly of a short was succeeded by the nitric acid process. At the period of about fifty-five days, brachypleionian waves;
present day chlorine is the predominant agent for partly of a long period of twenty years or so, macro
parting gold from silver in Australia, electrolysis in pleionian waves; and partly of an intermediate period
America, and sulphuric acid in Europe. of between one and two years, pleionian waves.
The electrolytic process was brought forward by In dealing with the longer periods the normal
Charles Watt, at Sydney, in 1863, and was first pu annual variation is eliminated by taking a series of
into operation by Wohlwill at Hamburg in 1878 and means for twelve months beginning with each con
by Tuttle at the Philadelphia Mint in 1902. In the secutive month of time. For the European stations
gold chloride process the solution used in the bath he finds that the continental ones resemble Arequipa
. Abstract of the presidential address delivered before the Institution of in having marked pleionian waves, while those sta
Mining and Metallurgy on March 18, by Sir T. K. Rose.
contains gold in the form of chloride and some free hydrochloric acid. Gold is dissolved at the anode, under the action of a current of electricity, and deposited in a pure state at the kathode. Other metals are also converted into chlorides at the anode, and either remain in solution, or pass into the anode slime. When silver is contained in the anode, it is converted into silver chloride which in part dissolves, in part falls to the bottom of the cell, and in part adheres to the anode, forming an insoluble coating.
The result of the coating is that the free area of the anode is reduced, the density of the current becomes greater per unit area of effective anode surface, and chlorine is evolved unless a very small current is used. According to general experience, if more than 6 per cent. of silver is present in the bullion of the anode it is necessary to brush the silver chloride from the anodes, and accordingly this percentage is seldom exceeded in practice.
square metre, the gold is deposited in a coherent form, which is easily. washed, and is malleable after being melted. The density of current now employed in practice is below 1000 amperes per square metre, and the anodes occupy about a week in being dissolved. With a current of 5000 amperes, the anodes would be dissolved within the limits of a working day and a saving in interest, and in the difficulties of daily stocktaking, would be effected.
One of the merits of the electrolytic process is that the refined gold is always malleabie and.fit for use in the arts, and another is that any platinum contained in the gold is extracted. This is becoming of some importance in view of the high price of platinum and of the fact that nearly all rough gold bullion, including that from the Transvaal, is now known to contain that metal. According to the experience in the United States mints (Fig. 1), it is cheaper to refine gold by electrolysis than by sulphuric acid.
the ninth of a projected series of ten reports setting forth the imposing mass of data regarding bird-migration collected by the committee appointed for the purpose by the British Ornithologists' Club. Once the final volume, dealing with the autumn of 1913 and the spring of 1914, has appeared, we may expect a publication of greater importance, summarising the vast amount of material collected by ten years' labour. In the meantime no attempt is made to draw conclusions from the facts which published, but a few points about the movements 1912-13 may here be selected for notice.
The autumn of 1912 Photo ] Fig. 1.- Electrolytic gold cells, United States Assay Office, New York. (B. P. Wirth. appears to have been
remarkable for the early dates at which
the The usual amount of free hydrochloric acid present migrations of several species began. Thus a swallow in the bath varies from 3 to 10 per cent., but accord- was noted at the Bell Rock Light in the Firth of Tay ing to the results of experiments now put forward on July 4, and willow-warblers at the same place two by Sir Thomas Rose some advantages are obtained days later. As early as June 25 a large flock of by the use of stronger solutions. Thus in a bath starlings had been seen flying west in the evening at containing 29 per cent. of free hydrochloric acid, a Spurn Head Light. On the nights of July 14-15 and current of 5000 amperes per square metre of anode 15-16 swifts were recorded from the Lundy North surface can be used without causing chlorine to be Light (British Channel) and the Hanois Light evolved at the anode. Under these conditions the (Channel Islands) respectively. proportion of silver in the anode may be raised to at The great movements, however, do not seem to least 20 per cent. without difficulties being encoun- have begun until mid-October, and the migrations tered. The heavy current causes the silver chloride observed during the first three weeks of November to split off from the anode, and also prevents gold were of extraordinary magnitude. Almost every night from entering the anode slime, principally because no during that period half-a-dozen different light-stations monochloride of gold is allowed to form.
record the passage of large numbers of birds, notably Similar advantages occur in the deposition of gold skylarks, starlings, and various species of Turdus. at the kathode by the use of a solution containing 1 Report on the Immigrations of Summer Residents in the Spring of 1913; 20 per cent. of gold as chloride instead of the usual
also Notes on the Migratory Movements and Records received from Light
houses and Light-vessels during the Autumn of 1912. (Bulletin of the 3 to 5 per cent. With a current of 5000 amperes per British Ornithologists' Club, vol. xxxiv., December, 1914.)
The winter which followed was.marked by com- interprets from his data. For copper he gives five paratively high and uniform temperatures. Conse- maxima and five minima. The fact, however, that quently many summer-visitant büds do not seem to these do not by any means always correspond to have quitted some of the southern and western observed points gave rise to considerable criticism in districts, while others were recorded as returning at the discussion and to a variety of alternative interpreunusually early dates. The spring immigration ::.
tations. From the fact that annealing greatly reduces proper is stated to have lasted from March Ô until the maxima and minima the author concludes that June 6, reaching its. hright between April 14 and work plays an important part in emphasising transMay 11.
formation points, and goes so far as to say that Attention is directed to the very long period covered "except in the case of phase changes in alloys, by the immigrationis of certain species as contrasted mechanical tests are to be preferred to heating and with those of others. On one hand we have swallow cooling curves as a means of studying changes of state (March .8 18: May 20), sand-martin (March 13 to May with temperature.” Even if this claim is admitted, it 15), chill-chåff (March 6 to May 8), and wheatear limits the application of such methods to ductile alloys, (Marib, ia to May 12). On the other we have the but not unnaturally objections were voiced to a state. reed warbler (April 18 to May 5), wood-warbler (April ment which has certainly not been proved. 9 to May 11), and nightingale (April 13 to May 5). Dr. Rosenhain, in his paper, entitled "Some Appli
A special feature of the report is the long list of ances for Metallographic Research," described an records emanating from the Caskets Light in the optical instrument for the levelling of metallographic Channel Islands. This station is exceptionally favour- specimens, a new method of taking thermal curves, ably situated, and was expected to furnish very im- and a plotting chronograph, the last-named having been portant data. Unhappily, the committee had formerly devised with the help of the Cambridge Scientific In, been unable to induce the light-keepers to take the strument Co. These appliances have been originated matter up. The desired result has been brought by Dr. Rosenhain at the National Physical Laboraabout, however, by the transfer to the Caskets of an tory. Great interest was expressed in them, particuenthusiast in the work, Mr. R. E. Wilson. His con- larly in the design of furnace for taking thermal tributions to the present report are very valuable. A curves. In order to obtain as nearly as possible a special summary of the records relating to this station
constant rate of heating or cooling of the metallic is promised for the next report.
specimen a tubular furnace is erected vertically, in The publication under discussion is even bulkier which a "regular temperature gradient is established than its recent predecessors, but the data are set out and steadily maintained while the specimens whose in the same clear and orderly manner. As usual there heating and cooling curves are to be taken are moved are numerous charts and a useful summary of the at any desired rate from the cold to the hot end of meteorological conditions prevailing during the period the furnace or vice versa."
Heating and cooling covered by the migration records
A. L. T. curves obtained in such a furnace and in conjunction
with the plotting chronograph show that very satisTHE INSTITUTE OF METALS.
factory results have been obtained. The power con
sumption with the hot end at 1000° C. is a kilowatt. IN N spite of the war, both the number and quality No figures for higher temperatures have been given,
of the papers presented at the annual meeting of and it will be interesting to have those stated when the institute on March 18 and 19 were well up to the they have been determined. average. Naturally, in the circumstances, the con- With regard to the plotting chronograph, the tributions were furnished mainly by what may be author's endeavour has been to originate termed the “ academic" workers in non-ferrous metall- ment which shall furnish an inverse rate curve "plotted urgy. Moreover, although the attendance of members
to an adequately open scale." The apparatus is not was small, the discussions were always interesting and as yet entirely self-recording, but represents a conwell-sustained. Unfortunately the president of the siderable step in this direction, and it gives the curve institute, Engineer Vice-Admiral Sir Henry Oram was obtained with no other human intervention than the prevented by his onerous official duties at Whitehall periodic tapping of a key. from presiding at the proceedings, and his place was The paper by Prof. Read and Mr. Greaves, of filled at the last moment by one of the vice-presidents. University College, Cardiff, contains an account of The paper by Prof. A. Huntington, on the effects
their investigations on nickel-aluminium and nickel
. of heat and of work on the mechanical properties of copper-aluminium alloys, more particularly the light metals, gave rise to an interesting debate, and a
alloys of the last-named group, and is a continuation spirited reply by the author. It describes a machine
of their earlier work on the heavy alloys of the same devised by him several years ago for the purpose of metals. They find that, as regards the ternary alloys, investigating these effects while the metals are being copper and nickel can replace each other without the subjected to alternating, bending stresses, such as resulting properties being affected, and, in fact, that occur in the firelox of a locomotive. No attempt was certain characteristics of the alloys are determined by made to reproduce the somewhat complicated move- the total percentage of copper and nickel present. As ments which occur there, but the metal or alloy was they point out, this is intelligible in view of the fact held rigidly at one end, and “subjected to a to and fro that the two metals possess almost identical densities movement at the other end in a single plane at right
and very similar atomic volumes. Moreover, microangles to its axis." Both as regards the extent of graphic analysis shows that the internal structure of the movement and the range of temperature investi- the alloy scarcely alters when the one metal replaces gated, the experiments were made to conform broadly the other. Inasmuch as nickel costs about three times to the kind of conditions that obtain in locomotive
as much as copper, and its melting point is nearly fireboxes. Various kinds of commercial copper, and 400° C. higher, it is clear that it cannot compete with a copper alloy containing upwards of 5 per cent. of
it economically in the case of such alloys, except pernickel and iron, were tested in this way. The out
haps in a few instances where the need for resistance standing feature of the curves, the co-ordinates of to corrosion in certain liquids is sufficiently imperative which are temperature and the number of revolutions
to outweigh considerations of expense. required to crack and break the specimens, is the A very useful compilation of etching reagents and large number of maxima and minima which the author their applications to metallography was presented by
Mr. O. F. Hudson. This work had been undertaken developments on a small scale which have been at the request of the Publication Committee of the originated here, have gone forward to new developinstitute, and in preparing it Mr. Hudson received and ments with increased vigour and with highly successincorporated methods adopted by well-known workers ful results. both in America and this country. The paper deals more especially with the final stage in the preparing (1) Provision of Glass APPARATUS FOR EDUCATIONAL of specimens for microscopic examination, but as the
PURPOSES. author points out, the effects of previous operations In the past practically all the glass and procelain must always be borne in mind. "There is now an apparatus used in chemical laboratories in this country increasing consensus of opinion among the most skilled has been manufactured in Germany and Austria. As metallographers that grinding on mechanically-driven the supply is now cut off and the stocks held by discs produces too severe an alteration in the surface British dealers are almost exhausted, the problem of structure of a metal or alloy, which is likely to create obtaining apparatus for educational and technical purdifficulties in their microscopic interpretation after poses has become a serious one. etching, and that hand grinding, although slower, is The Joint Committee is informed that efforts are much more trustworthy. This is neither more nor less now being made by several firms to introduce the than a return to the technique of the late M. Osmond, manufacture of glass apparatus into this country, and whose skill in the preparation of a specimen for micro- being in hearty sympathy with these efforts, it has scopic examination has never been surpassed. The considered in what way the British Science Guild may discussion on Mr. Hudson's paper was in a high best assist. In these efforts the committee has codegree illuminating, and showed the institute members operated with the Association of Public School Science at their best. When the complete paper and dis- Masters, and has taken action along two main lines, cussion are published they will certainly be a standard
viz. :work of reference.
(A) Endeavouring to obtain assurances of support Four other papers were submitted. Of these, that for British makers of educational glass ware after the by Mr. Whyte, on the microchemistry of corrosion, and war as well as now. that by Mr. Haughton, on the constitution of the (B) Obtaining information from educational insti. alloys of copper with tin, were read and discussed. tutions respecting the principal types and sizes of glass The remaining two were taken as read, and will be apparatus in greatest demand. discussed by written communications.
H. C. H. CARPENTER.
(A) Assurances of Support for British Makers of
Scientific Glass Ware.
It is understood that the efforts during the last SUPPLIES OF LABORATORY AND
three months by certain British glass manufacturers
have been attended with satisfactory results as regards OPTICAL GLASS APPARATUS.
the quality of the products. Economic and manufacREPORTS OF THE BRITISH SCIENCE GUILD. turing conditions have prevented British glass appa
ratus being sold at so low a price as has been paid THE HE British Science Guild has just issued two in the past for German material. As these conditions
reports dealing with matters of national moment will probably remain unchanged, British manufacat the present time. One is concerned with the pro- turers have been naturally disinclined to expend the vision of glass apparatus for educational purposes, necessary capital in establishing the proposed new and the other with optical glass and the position of industry here while there is every likelihood that they technical optics generally in this country. The re- will be undersold in the British market by their comports are here reprinted, and it will be seen that they petitors when the war is over. The Joint Committee are both informative and helpful. First, with regard is informed that this has acted as a strong deterrent to laboratory ware, it appears that, as the result of an to British glass manufacturers contemplating the proinquiry instituted by committees of the guild, working duction of scientific glass apparatus. in co-operation with the Association of Public School The Joint Committee therefore has endeavoured to Science Masters, about three-quarters of the schools ascertain how far it is probable that educational instior other bodies requiring laboratory glassware have tutions would undertake to buy only British-made undertaken to use British glass during the war, and glass and porcelain apparatus during the war, and for for a period of three years after, provided that the a period of three years after. price is not prohibitive. As explained in a letter to Inquiries were made in this direction by the hon. NATURE of February 18 (p. 670) the British Labora- secretary of the Association of Public School Science tory Ware Association has made arrangements for Masters, who is a member of the Joint Committee. the supply of laboratory glassware and similar mate- from the headmasters of all schools represented on the rials from British manufacturers. The British Science Headmasters' Conference. Out of the hundred and Guild has, by its action, presented the association ten (110) schools so represented, no fewer than seventyand British glass manusacturers generally with an eight (58), i.e., 71 per cent., have definitely promised assurance of support which should be of the greatest to authorise their science staffs to purchase, as far as value to them.
possible, only British-made glass apparatus during The report of the Technical Optics Committee of and for a period of three years after the conclusion of the guild should cause serious attention to be given
As these promises have been received from to the establishment of a British Institute of Technical almost all the largest schools, both boarding and day, Optics. In the last annual report of the guild it was it may be assumed that manufacturers as well as pointed out that this necessity had been impressed | dealers will receive adequate support from the conferupon the education department of the London County ence schools." Council continuously during the past twelve years. The guild also issued about 750 letters of inquiry Scientific experts, leading members of the optical to industry, and educational experts have combined to (a) Local education authorities. urge the paramount importance of the definite pro- (b) Governors of secondary schools. posals which have been formulated, but the scheme (c) Governing bodies of technical institutions. still hangs fire. Meanwhile our scientific and indus- (d) Senates of universities and university colleges, trial rivals on the Continent, taking note of successful and has received a very large number of replies.