THE LATE CAPTAIN BASEVI, R.E.

A LETTER in the Times of the 19th inst., from Col. J. D. Walker, R.E., announces the death of Captain James Palladio Basevi, of the Royal (late Bengal) Engineers, DeputySuperintendent of the Great Trigonometrical Survey of India, an officer of great worth and ability, whose loss will be long felt in the department of the public service to which he belonged. He was the son of the celebrated architect, George Basevi, and was distinguished as a lad for more than ordinary talent, and particularly for his mathematical abilities. First at Rugby, then at Cheltenham College, and afterwards at Addiscombe, he won for himself a high position among his fellow students, and in December, 1851, he left Addiscombe as the first cadet of his term, obtaining the first prize in mathematics, the sword for good conduct, the Pollock medal, and a commission in the Honourable East India Company's Corps of Engineers.

The first few years of his services in India were spent in the Department of Public Works in the Bengal Presidency; but in 1856 he was appointed to the Great Trigonometrical Survey of India, in which he continued to serve up to the time of his death, performing many services of great value.

His bent of mind and habits of study led him, however, to feel a preference for the more purely scientific branches of the operations of the Trigonometrical Survey. Thus, in 1864, he was selected to undertake certain operations which had been proposed by the President and Council of the Royal Society for the determination of the force of gravity at the stations of the great meridional arc of triangles measured by Lambton and Everest, which extends from Cape Comorin to the Himalayan Mountains. The investigations were to be effected by measuring the number of vibrations which would be made in a given time by certain invariable pendulums when swung at the several

stations.

Captain Basevi entered on the pendulum observations with his characteristic ardour and devotion. He carried his observations of pendulum and clock coincidences over at least twelve days at each station; for ten hours daily-from 6 A. M. to 4 P.M.-he never left his pendulums for more than a few minutes at a time, taking rounds of observations at intervals of an hour and a half apart; then at night he would devote a couple of hours to star observations for determining time.

His observations of the pendulums on the Indian arc showed that the local variations of gravity which are superposed on the great law of increase from the equator to the poles, though apparently irregular when examined singly, are subject to laws which are highly interesting and curious, and are well worthy of investigation. At the northern extremity of the arc the results indicate a deficiency of density as the stations approach the Himalayan Mountains, while at the southern extremity they indicate an increase of density as the stations approach the ocean; thus both groups of results point to a law of diminution of density under mountains and continents, and an increase under the bed of the

ocean.

Thus far, however, observations had not been taken at any very great altitudes, the highest station in the Himalayas being under 7,000 feet; arrangements were therefore made to swing the pendulums on some of the elevated table lands in the interior of the Himalayas, which rise to altitudes of 14,000 feet to 17,000 feet. It was expected that this would be sufficient to complete the work in India, and then the pendulums would be taken back to England to be swung at the base stations of Greenwich and Kew, and en route at Aden and at Ismailha on the Suez Canal, places which are in the same latitudes as some of Captain Basevi's stations. Thus gravity at Aden would be directly com pared with gravity at certain points of the coast and continental stations of the Indian Peninsula, and similarly the plains of Egypt would be compared with the Himalayan Mountains.

In the spring of the present year Captain Basevi proceeded to Kashmir on his way to the high table lands in the interior. Early in June he reached Leh, the capital of Ladak. He then

proceeded to the Khiangchu table land in Rukshu, about eighty

miles to the south of Leh. There, at a spot called Moré, in lat. 33° 16′ and long. 77° 54′, and at an altitude of 15,500ft., he completed a satisfactory series of observations, which show a very gross deficiency of density. After applying the usual reductions to sea level, &c., it was found that the force of gravity at Moré did not exceed the normal amount for the parallel of latitude 6° to the south, as determined by the previous observations with the same pendulums.

Wishing to have one more independent determination at a high altitude, Captain Basevi proceeded to the Changchenmo Valley, which lies due east of Leh, across the newly-proposed trade route between the British province of Lahoul and the States of Eastern Turkestan. Near the eastern extremity of that valley, on the confines of the Chinese territories, he found a suitable position in lat. 34 10 by long. 79'25, at an altitude which is not exactly known, but must probably have exceeded 16,00oft. He hoped to complete his observations in ten days, and then commence the journey back to India. But he did not live to carry out his intentions; already the hand of death was upon him, and, all unconsciously to himself, the over-exertion to which he was subjected in a highly rarefied atmosphere and under great vicissitudes of climate was rapidly undermining a constitution which, though vigorous, had already been sorely tried.

With the devotion of a soldier on the battle-field, he has fallen a martyr to his love of science and his earnest efforts to complete the work he had to do, and in him we have lost a public servant of whom it may be truly said that it would not be easy to find his equal in habitual forgetfulness of self and devotion to duty.

SOCIETIES AND ACADEMIES

PARIS

Academie des Sciences, Sept. 11.-M. Faye in the chair. -M. Dumas read an abstract of a pamphlet published by MM. Lomer and Ellershausen, advocating the establishment at Bellegarde, in the department of Ain, of hydraulic machines worked by the Rhone, and giving a force of 10,000 horse-power. The site is called "Le perte du Rhone" at Bellegarde, and this immense hydraulic pressure is to be obtained by boring a tunnel, through which only one-third of the water of the Rhone will go. The height of the fall will be sixty feet, and the result is to be obtained very easily, as the tunnel is only to have a length of 550 yards. The engineers hope to create at Bellegarde a city as important as Lowell in the United States. It is intended to induce Alsatian manufacturers to move from Mulhaus, and to settle in that locality. M. Decaisne sent some observations relating to animals fed with bread infested with the oidium aurantiacum, and it is considered as demonstrated that, at least under special circumstances, such food must be considered as being really poisonous. -M. Berthelot sent a very long paper on the union of alcohol with bases, which was inserted in extenso in the Comptes Rendus. -M. Lecoq de Boisbaudron sent also a paper which was published by him some time ago, on the constitution of luminous spectra. -M. Favre sent a paper to elucidate certain points of a special theory worked out to explain how a certain weight of copper rotating between the poles of an electro-magnet is heated by the influence at a distance. The fact was discovered by Foucault.

SAN FRANCISCO

California Academy of Sciences, August 22.-Mr. Dall called the attention of the members to some shells of oysters that had been transplanted from the Eastern States, and which during the last twelve months had been growing in the waters of the bay. The recent growth of these oysters had been modified in a manner so that they corresponded very closely to that of our native oyster. In the eastern oyster the shell is white and smooth, whilst our bay oyster has the shell much corrugated, of a brown colour, and frequently with purple stripes between the ridges. Now the recent growths of the shell of these transplanted eastern oysters exhibit the same corrugations as our na tive, the colour is decidedly more brown than in the east, and purplish stripes are frequently found between the corrugations. -Dr. Blake gave a description of some prismatic dolerite found in the neighbourhood of Black Rock, Nevada. The prisms were six-sided, measuring from o'r in. to 0.3 in. across, and some were from 3 in. to 4 in. long, but they all had evidently been

perhaps the most suggestive portion of this original work. In short, the experimental method is adopted in every chapter; and it is thus that the inquirer after truth is taught, step by step, to appeal to the fountain source for most, if not all, information concerning "the wonder and mystery of Nature."

There is, however, a very marked disproportion in the amount of space allotted to each subject. Machines occupy only sixteen pages-probably the feeblest chapter in the book; while Crystallography extends over as many as thirteen pages. We think also that too much attention (relatively, at least) has been paid to Electricity and Magnetism. Pure and simple observation, even of natural phenomena, cannot properly be said to educate the mind, unless the reasoning faculties are called into play; and such subjects as Electricity, Botany, and Crystallography, if made an essential portion of school training, would doubtless tend to bring the whole question of science-teaching into disrepute. The only experiments that should be performed in the laboratory are such as will bring to light a scientific fact; and it should be remembered that a fact is scientific only in so far as it is interconnected with other facts. The more intimate this interconnection is, the better suited is

the fact for elementary education; because it gives rise to a greater amount of rational explanation, and tends, by reaction, to imprint upon the mind knowledge already acquired. Professor Hinrichs does not appear to us to attach sufficient importance to these views; his work has therefore a disjointed aspect, and is wanting in large general ideas which should be cautiously introduced at proper intervals for the purpose of increasing the scope of the pupil's understanding. We agree with him that the quantitative study of such subjects as the Law of Gravitation should be postponed to the last year of the school course; but its qualitative study might be carried on with great advantage at a much earlier period; for previous familiarity with such theoretical views as are capable of some sort of experimental proof will make a student anxious to examine the subject quantitatively at the earliest opportunity. For these reasons we regret to find certain, points omitted in the present volume, such as the Laws of Motion, which are so admirably adapted, not only for experimental verification, but as a means of explaining the principles of scientific induction. Still, if Prof. Hinrichs has not discovered every gem, he has nevertheless succeeded in pointing out the right path of discovery, along which he has acted on the whole as a faithful and thoroughly painstaking guide.

The idea of the "School Laboratory" is also a very admirable one. It is, in fact, a monthly magazine, the aim of which is to inculcate the system of experimental work upon which Prof. Hinrichs so strongly insists; to give examples of methods and results; and to aid both teacher and pupil.

We trust that the efforts of this able reformer of scienceteaching will be amply seconded; and we believe that these Elements will be found of great service to every conscientious teacher, who will be able to glean from them many valuable suggestions both as to method and treatment; and we recommend them especially, because a widely-spread knowledge of a work of this kind will tend very much towards the introduction of experimental

science into the curriculum of our schools.

OUR BOOK SHELF

Phrenology, and how to use it in Analysing Character. By Nicholas Morgan. (London: Longmans, Green, and Co. 1871.)

THE appearance of a book of this kind from time to time shows what a deep hold phrenology took upon the popular mind. Had it not been so, we should have neither writers nor readers of works upon "The Science of Phrenology," now that almost the whole foundations of the system have been shown to be either untrue or based upon misconceptions. The present work is illustrated by numerous portraits and other engravings, and several of the former are remarkably truthful representations of living or recently-living celebrities; though we doubt whether the accompanying analyses of character will prove as agreeable to the originals as they are destined to be edifying to the public.

The Dependence of Life on Decomposition. By Henry Freke, M.D., T.C.D., &c., Professor of the Practice of Physic and Lecturer on Chemical Medicine in Steven's Hospital Medical College. (London: Trübner and Co.) THIS is a pamphlet of a controversial character, which would not prove interesting to the general reader. Dr. Freke's views were originally published in 1848 in a work "On Organisation." They are peculiar in many respects, but contain the germs of some important biological truths. The following passage (p. 28) may serve as an example :"Why, with an adequate supply of food, are we not able to work our brains, muscles, &c., for an indefinite period, like a steam-engine with an adequate supply of steam? Because the tissues are disintegrated, and require nutri tive repair. If the animal tissues did not undergo disintegration during the active discharge of their functions, why should not the animal, like the vegetable, continue to increase in dimensions during the entire period of its organic existence? It is because the organic tissues developed by the vegetable do not undergo disintegration when their construction has been completed, that the vegetable continues to grow and increase in dimensions during its entire life. Such is not the case with the animal, and that for this reason, namely, when the construction of the animal tissues, brain, muscle, &c., is com pleted, those tissues undergo disorganisation while discharging their functions."

The Estuary of the Forth and adjoining Districts viewed Geologically. By David Milne Home, of Wedderburn. (Edinburgh: Edmonston and Douglas.) MR. MILNE HOME'S name has long been known in con nection with Scottish geology. His memoir on the Coalfields of the Lothians was for many years the only trustthis he has from time to time communicated to various worthy geological account of those areas. In addition to scientific journals a number of papers chiefly on subjects relating to glacial geology. In this present volume he returns to these subjects, and gives us a description of the superficial formations of the basin of the Forth, together with what he considers to be the most feasible explanation of the somewhat intricate details he brings before his readers. He treats first of the form and physical features of the Estuary and the districts adjoining; secondly, of the formation or origin of the Estuary; and, thirdly, of the superficial deposits met with in the area described. He conceives that the faults which intersect the strata along both sides of the Firth, and which not only have the same general bearing as the Estuary, but are also for the most part downthrows to south, in Fileshire, Clackmannan, &c., and, in the Lothians, downthrows to north, have formed the deep trough or valley of the having reached at least 2,000 feet. "Along the lines of Forth-the depression caused by this series of step-faults these slips great precipices, or cliffs, were formed, several hundred feet in height, which, under the action of the sea

or the atmosphere, crumbled down." The materials thus supplied went to form the superficial deposits, it being supposed that almost the whole of Scotland was under the sea at the time these changes took place. We feel sure that Mr. Milne Home will get few geologists to agree with him in these conclusions. In the first place, it may very well be doubted whether the faults which cut the strata ever actually showed at the surface in the manner supposed. It is much more probable that the dislocations took place so gradually that any inequalities arising therefrom were planed away by denudation as fast as they appeared. But even were this not the case, it is quite certain that the faults referred to by Mr. Milne Home must date back to a vastly more remote antiquity than the later Tertiary periods. The Scottish Coal-fields, indeed, would appear to be traversed by some faults which, according to the Geological Survey's map and description of the South Ayrshire Coal-fields, do not influence the overlying Permian. It is also indisputable that the igneous dykes, which Professor Geikie has shown to be of Miocene age, are all posterior in date to the faults which shift the Coalmeasures. Mr. Milne Home does not take into consideration the prodigious amount of denudation that the paleozoic strata of the valley of the Forth must have undergone in the long ages that intervened between the close of the Carboniferous period and the advent of the glacial epoch. There cannot be any reasonable doubt that the valley of the Estuary of the Forth existed as a valley long before the dawn of the age of ice. But Mr. Milne Home's memoir is taken up chiefly with the history of the drift deposits, which he describes in considerable detail. Especially valuable are the numerous sections given, and the long lists of localities where glacial-striæ, erratic blocks, kaims, and the other phenomena of the drift, may be studied. The author inclines to the iceberg theory of the formation of the boulder-clay, and thinks it may have originated at a time when "the ocean over and around Scotland was full of icebergs and shore-ice, which spread fragments of rocks over the sea-bottom, and often stranded on the sea-bottom, ploughing through beds of mud, sand, and gravel, and blocks of stone, and mixing them together in such a way as to form the boulder-clay." Mr. Milne Home points to the presence of beds of sand included in the boulder-clay as one of several objections to the landice origin of that peculiar deposit. He thinks that if the iceberg theory be adopted, the explanation would be simply this, "that icebergs came at different periods, new sea-bottoms being formed in the intervals." But, on the other hand, if the glacier theory be accepted, then it would have to be admitted that the land must have sunk under the sea for every bed of sand we find in the boulder-clay. The author, however, does not seem to be aware that fresh-water beds are found interstratified with the boulderclay, so that the difficulty in either case is equal. We have not space to notice several other interesting points treated of in this memoir, which contains so many important data, that we can recommend it confidently to our geological readers. We may dispute some of the author's conclusions, but it matters not what interpretation may eventually be put upon the facts, many of the facts are here, and Mr. Milne Home has done good service in bringing them together. J. G.

LETTERS TO THE EDITOR

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

Phenomena of Contact

IN NATURE for August 24, Mr. Stone controverts two propositions incidentally put forward in a review of Mr. Proctor's book, "The Sun." They are:

"2. That when seen they are due to insufficient optical power or bad definition."

In writing that review, I tried to avoid the assertion of any proposition I could not fully sustain, and therefore very willingly give the evidence on which these propositions rest. At the outset, however, I beg leave to call especial attention to the fact that I did not assert the second in an absolute manner, but only said that it was "indicated" by observations and experiments.

The first proposition is sustained by the fact that at the last transit of Mercury, the majority of those observers who have described the phenomena saw neither ligament nor distortion, but only the geometrical phenomena of contact, the planet preserving its rotundity to the last.

The following is a statistical summary of the evidence on both sides-Among the numerous English observations published in the monthly notices, fourteen describe the phenomena. Of these three saw the phenomena go on regularly, while eleven saw ligament, black drop, or distortion either before or after the contact. Among these eleven there is little agreement as to the exact nature of the distortion. Owing to the low altitude of the sun in England, I take it that the atmosphere was much less favourable than on the Continent.

At Marseilles Le Verrier saw the black drop. He used a seven-inch glass, of which both the centre and circumference were covered by a screen, which is sufficient to account for the phenomenon by the diffraction thus produced. Mr. Stephen, who observed at the same place with a very large reflector, "déclare n'avoir rien vu de pareil.'

Of the five observers at the Paris Observatory, Le Verrier sayst:-"Les observateurs ont remarqué qu'il ne s'est rien présenté de particulier, ni au moment du contact intérieur, ni après ce contact. Mercure a touché le bord du Soleil en amincessant progressivement le filet de lumière, mais sans produire le phénomène de la goutte." Le Verrier was, therefore, so far as we know, the only observer in France who saw the black drop. At Madrid Ventosa may have seen several black drops "toutà-coup." His description, however, is rather obscure. + At Lund the egress was observed by Duner under very favourHe says §:-" Die able circumstances with a nine-inch glass. Bilder waren sehr ruhig, und die innere Berührung geschah in der

Weise, dass der Lichtfaden Zwischen den Rändern des Mercurs

und der Sonne erst dann brach als seine Breite verschwindend klein geworden war. Es zeigte keine Spur einer Verdrehung der Bilder oder des von anderen Beobachtern erwähnten schwarzen Tropfens.

At Pulkowa fourteen observers observed the egress. I learn that not one saw anything but the geometrical phenomena of

contact.

To avoid a tedious collation of accounts which nearly all say the same thing, I remark that only two observers on the Continent saw any abnormal phenomena, namely, Kaiser at Leiden, and Oppolzer at Vienna. The first saw an elongation of the planet, which he thought might be due to maladjustment of his instrument. The second saw the sun's limb pushed out by that of Mercury, so that apparent contact took place before the breaking of the thread of light.*

**

39

Summing up all the accounts, I find the result to be:Total number of observers who describe phenomena Number who saw the planet remain perfectly round, and the phenomena of contact occur with entire regularity, and without distortion, ligament, or drop 24 Number who saw ligament, distortion, one or more drops, or other abnormal phenomena . . 15

The twenty or thirty observers who do not describe the phenomena probably saw nothing abnormal, but they are not counted in the above list.

The first proposition is, I conceive, fully established by the statistical facts cited.

Passing now to the second, it may be remarked that when different observers give different descriptions of the same

* Comptes Rendus, 1868, ii., p. 921-924.

+ Ibid. p. 948.

↑ Astronomische Nachrichten, vol. Ixxii., p. 356. Ibid, p. 378.

Il Ibid, vol. lxxiii., p. 214. **Ibid, vol. lxxii., p. 347.