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THE BRITISH ASSOCIATION AT CAMBRIDGE.
BY PROFESSOR D. T. ANSTED, M.A., F.R.S.
THE late meeting of the British Association, held during the first week
of October in the University of Cambridge, has been one of those that may be regarded as successful, both in reference to the scientific men present and the communications made. It was not large, numbering only about 1,200 members in all; but the absentees, though including some wellknown and familiar names, were chiefly the amateurs of science, associates, ladies, and those who join only for the current meeting; not working members, to whose labours the meetings are chiefly indebted for their important practical results. The sections were fairly attended, without being crowded, except on some few special occasions. The evening meetings were also well attended; and although the monetary returns will hardly be very brilliant, the reminiscences of Manchester and the prospects of Newcastle will console the treasurer for the comparative emptiness of the purse on this occasion. The Association meets one year for itself and another for the place it visits. At Cambridge, on the occasion of this, its third visit, there was not much enthusiasm, but there was a very pleasant assemblage of numbers of old members, who had been long without seeing one another, but who were not less warm in their greeting than if they had been annual attendants and had kept up acquaintance by frequent visits to the annual reunion.
An absence of excitement and “sensation" certainly characterized the meeting. The President (Professor Willis), in his address, rather recalled attention to the early labours of the Association, and the fruits it had borne years ago, than to the present state of science.
The evening lectures were on subjects already worn somewhat threadbare by frequent repetition at the Royal Institution, and were certainly not complimentary to the Cambridge audience. It is much to be regretted that Mr. Glaisher's interesting account of his balloon ascents did not replace one of these, and that a notice of recent researches in some interesting department was not introduced in place of the other. In spite,
however, of these mistakes, the meeting was pleasant and satisfactory, and the communications and discussions not unworthy of the occasion.
Of the different sections, that known as A—Mathematical and Physical Science-offers the greatest variety of subjects, and receives a number of communications that do not properly belong to it. Some of these should be considered in E (Geography and Ethnology), and others, perhaps, in B (Chemistry). It is no doubt difficult to determine in many cases in what way to limit so very general a term as Physics. Including Astronomy and Magnetism and, perhaps, Meteorology, it is apt to absorb Physical Geography. In something of the same way, B (Chemistry) and C (Geology) occasionally overlap. D (Natural History), if strictly confined to Biology, would be tolerably independent, though not unfrequently there are links connecting it very closely with Geology by the medium of Palæontology. Physiology is regarded as a branch of Natural History, and Statistics (F), of course, finds place everywhere. Mechanics (G) is tolerably well defined. Omitting any reference to Section D, which is in other hands, I propose to recall some of the principal and more interesting communications and discussions, not so much in a systematic outline as in a general statement.
Mr. Glaisher's balloon report, already alluded to, was the most attractive paper of the meeting, and certainly included all the elements of a popular lecture. As a meteorological communication, it was given to Section A. There were several other papers of interest, connected with meteorology, climate, and other departments of Physical Geography, about which we may say a word; some being communicated to Section A, and others to Section E. It is to be regretted that a better arrangement is not made with regard to such papers. At a scientific meeting, Physical Geography should certainly receive more consideration than Descriptive Geography and Travels, to which the geographical part of E has been mainly reduced, while Climatology—too important a branch of science to be neglectedought not to be carried to general Physics, which is already too crowded with other matter more strictly belonging to it.
The balloon ascents of Mr. Glaisher are direct results of British Association work. It has long been felt, that to determine the condition of the upper part of the atmosphere, it was not sufficient to make observations on high mountains. In such cases we always carry the earth with us, and the mere existence of a mountain-chain is a serious cause of disturbance to the atmosphere. Even isolated conical peaks in detached oceanic islands are not satisfactory. On the other hand, the car of a balloon is not a very favourable station for observing ; the work required to be done involves unusual accuracy and rapidity of observation, and the instruments used are very liable to injury in the descent. A large balloon, great precautions in managing it, and repeated experiments by practised observers, were indispensable ; and these are not easily obtained. Moreover, the balloon is a costly instrument for experiment, and its use involves much danger to the inexperienced. The means, however, being furnished by an association grant of last year, an observer was found in Mr. Glaisher, than whom no man living is more fit for work of this kind.
It appears, also, that Mr. Coxwell has fully justified his reputation as
the first living aërial engine-driver. He is at once intelligent, instructed, and experienced, --sufficiently bold, but by no means reckless.
The number of ascents recorded is eight, and the average time in the air in each case was under two hours. The extreme height reached was above 30,000 feet; but there are no means of telling how much higher the balloon rose, as in this ascent Mr. Glaisher was, unfortunately, insensible from cold and exhaustion, during the critical time, and Mr. Coxwell was little better. The season of all the ascents was autumn, the dates ranging between the 18th August and the 8th September. The rate of ascent and descent was various, but sometimes extremely rapid, amounting to several thousand feet in a few minutes. The number of observations required to be made almost at the same moment, during the whole ascent, is enormous, but they seem to have been made with certainty, and without inconvenience, except at extreme elevations.
The conclusions arrived at, though only partial, were interesting and important; but they require confirmation and comparison with those made at another period of the year. The observations will probably be repeated in the spring of next year, and the results will be looked forward to with great interest at the Newcastle meeting.
Mr. Glaisher's account is graphic in the extreme, and the effects he saw on some occasions, when the balloon rose above a mass of clouds into the clear blue vault of heaven, are described as altogether surpassing in grandeur and beauty any cloudscapes visible from terra firma. This part of his narrative has, however, been frequently quoted in the daily newspapers and weekly journals, and need not be repeated.
Among the scientific results obtained by these balloon ascents are the following :-1. There seems no wind blowing steadily with any uniformity of direction in the upper regions of the air over our island at any height yet reached. 2. The clouds do not seem to form according to the contour of the land, but do seem to follow the tide up the great rivers. 3. The temperature not only does not decrease regularly as greater height is attained, but, in some cases, a very low temperature was attained near the earth, and was succeeded by much warmer air at far greater elevation. 4. The aneroid barometer may be used with advantage, and may be depended on to any attained height. Mr. Glaisher states that it is available to a pressure of only five inches of mercury. 5. The humidity of the air diminishes rapidly, and at a height of five miles is extremely small. Several suggestions were made by various members in reference to aërial navigation generally, and the whole subject was recognized as of the greatest importance.
Memoirs were communicated on Climatology and Meteorological Instruments by Mr. G. J. Symons, Mr. Plant, Professor Ansted, Dr. Gladstone, Mr. Galton, Mr. Lowe, and other members. Some of these were of much interest, but we have not space to allude further to them. Mr. Lowe's paper on Ozone was especially valuable, and included the description of a new Ozone box, showing some interesting results.
The structure of the sun's surface and the volcanoes of the moon were the subject of several communications. Mr. Nasmyth pointed out some recent observations tending to prove that the sun's nucleus is dark and dense ;
the light emanating from an outer envelope of lenticular filaments, not distributed in symmetrical order. He estimated these filaments at about 1,000 miles long by 90 miles broad, and stated that they move among themselves with enormous velocity, separating to form spots, and filling in to obliterate them. They are regarded by Mr. Prichard as solid. Some admirable representations of lunar volcanoes were exhibited and described.
On the whole, not less than seventy-six communications were referred to Section A, this being more than one-fourth part of all memoirs received, and more than double the number read at any section but Geology. Of these, at least twenty were strictly meteorological, and belonged much more to Physical Geography than to General Physics. In Section E (Geography and Ethnology, including Archäology) there were in all only twenty-eight memoirs, and of these only four related in any way to Physical Geography, while seventeen were mere narratives of travel.
In Section B, the communications were not of popular interest, and were chiefly technical. There was, however, one paper, by Mr. Lawes and Dr. Gilbert, on the subject of Manures and their action on grass land, interesting to the agriculturist. Many of the geological communications and discussions were also technical; but, as usual, there was a sufficient sprinkling of popular matter to attract strangers and ladies. Perhaps the most interesting novelty was the notice of Dr. Falconer's pigmy-elephant bones, of which some were obtained, three years ago, from a cavern in Malta, by Captain Spratt, R.N.,and retained quietly by Dr. Falconer till a sufficient number of specimens had been received to decide every point of structure. There was something unusually interesting in the result of this reticence. Instead of the usual announcement of a new species from a single tooth or fragment of a bone, Dr. Falconer, as soon as he obtained the first instalment of news regarding so curious a variety, simply put his specimens by, and urged his friend, Captain Spratt, to search for and send more. He sent more; but, still, other bones were wanted; and, at last, in this way, a series was got together which really left nothing to be desired. Then our cautious Doctor, who has made elephants his special study, found himself in a position to bring down to the Association a perfect embarras de richesses in reference to this new form. He has bones and teeth of individuals of all ages, and, comparing them with corresponding bones and teeth of the Indian or fossil species, he exhibits all the peculiarities of structure. This pigmy was, when full grown, about the size of the Malay tapir, but was in all respects a true elephant in structure, having tusks and teeth in all respects elephantine. It inhabited Southern Europe up to a comparatively late tertiary period.
The drift question and the deposits of loose and alluvial mud in the bed of the Rhine and other rivers,—the gravel, and its connection with the glacial period, and the facts of chief interest in reference to this question, were the subject of many papers and of some very interesting discussion. This department of Geology is now clearing itself, and, before very long, will afford the latest, and probably the most instructive, chapter in all geological works. It still remains surrounded with difficulties ; but they will disappear one after another, and we shall then be able to connect the present with the past.
The subject of coal was introduced by Professor Ansted in two papers, one referring to a newly-discovered tertiary coal, of excellent quality and strictly bituminous, found in Hungary; and the other pointing out the difference between coal with bituminous schists. Dr. Sterry Hunt also made a communication on the subject of the Rock Oils of North America. But little discussion followed, and the question as to the origin of coal was not gone into. The discussions generally in the geological section were somewhat tame. Mr. Sorby communicated a very interesting addition to his observations on the structure of shells, pointing out that certain parts of the animal and certain animals habitually deposit carbonate of lime in the shape of aragonite, while other animals, and some other parts, deposit calcite. The aragonite form is not, however, so permanent as that of calcite, and hence it is apt to disappear or pass into calcite during fossilization.
Section E did not present much that was new. Sir R. Alcock, on Japan ; Sir C. Nicholson, on recent explorations in Australia ; Captain Burton and Mr. Jules Gerard, on African discovery,—all promised well, but failed to keep up the interest their subject matter seemed to offer. There was, however, an interesting communication by Mr. J. Wright, on an archæological subject, started at the Oxford meeting, arising out of the excavations on the site of the ancient Roman city of Uriconium, on the borders of Wales. Numerous human remains were there discovered, and of some of these the skulls are strangely and systematically distorted. As all the regular interments within the walls consisted of bodies that had previously been burned, the persons whose skulls remain were probably destroyed when the city was sacked and burned. The skulls of the Roman inhabitants seem not to be injured, but buried in a spot supposed to be an entrance to the town, and under circumstances which seem to show that they are certainly not older than the Roman period, and probably not much newer. There were found eleven skulls, seven of which were singularly and uniformly deformed, having an unnatural twist, which causes one eye to advance beyond the other, and gives an obliquity to the face. The cause of this has not yet been determined.
Several communications of great interest were made in Section F (Economic Science and Statistics). Among the most important, both for subject and treatment, may be mentioned one by Mr. Vernon Harcourt, on scientific evidence, and two or three, by competent authorities, on the course of studies and the expenses of student life at the University. Valuable and lively discussions took place with reference to all these.
It has long been felt that the position of a man of science called on to give evidence in a court of law is difficult and unsatisfactory. He receives his instructions and information on the question at issue from one side, and as there are few subjects that do not admit of two opinions, he naturally and inevitably makes the best of the case put before him. To some extent, he thus becomes an advocate, and his real judgment is biassed. It was proposed by Mr. Harcourt that, in place of scientific evidence, as now received, skilled assessors should be appointed by the judge on application, and that they should give their opinion in writing. Mr. Whiteside, Q.C., while admitting the necessity of some change in the