THE NEWALL TELESCOPE

THE HE 25-inch Equatorial Telescope, commenced several years ago by T. Cooke and Sons, of York, for R. S. Newall, Esq., of Gateshead, is now so far completed that it has been removed from the works at York into its observatory in Mr. Newall's grounds, at Fern Deal.

The completion of a telescope with an object glass of 25 inches aperture, marks an epoch in astronomy, and its completion in England again places us in the front rank in the matter of the optical art, as we were in Dolland's time.

The history of the progress of the manufacture of telescopes since the time referred to, shows very clearly the long-lasting effects of bad legislation; for it is not too much to say that the duty on glass entirely stifled, if indeed it did not kill, the optical art in England. Hence we depended for many years upon France and Germany for our telescopes to such an extent indeed that the largest object-glasses at Greenwich, Oxford, and Cambridge are all of foreign make. The labours of the Germans culminated in the two magnifi

cent instruments of 15 inches aperture in the observatories of Pulkowa and Cambridge, U.S. And then for a time America, thanks to the genius of Alvan Clarke, took the lead with the 18 inch glass now beginning to do good work in the observatory of Chicago. This instrument is at last eclipsed by the magnificent one now being erected at Gateshead.

In what we have said we have purposely omitted to touch upon reflecting telescopes, in the construction of which, since the time of Newton, England has always been pre-eminent, because we shall take occasion to refer to the reflector of four feet aperture, completed last year by Mr. Grubb, of Dublin, and now erected at Melbourne when it is fairly at work.

The general design and appearance of this monster among telescopes, which will be gathered from the accompanying woodcut, is the same as that of the wellknown Cooke equatorials; but the extraordinary size of all the parts has necessitated the special arrangement of most of them.

The length of the tube, including dew-cap and eye-end,

is 32 feet, and it is of a cigar shape; the diameter at the object-end being 27 inches, and at the centre of the tube 34 inches. The cast-iron pillar supporting the whole is 29 feet in height from the ground to the centre of the declination axis, when horizontal; and the base of it is 5 feet 9 inches in diameter. The trough for the polar axis alone weighs 24 cwt., the weight of the whole instrument being nearly 9 tons.

The tube is constructed of steel plates rivetted together, and is made in five lengths, screwed together with bolts and flanges. The plates of the central length are oneeighth of an inch thick, and those of each end onesixteenth thick, so as to reduce the weight of the ends as much as possible, and avoid flexure.

Inside the outer tube are five other tubes of zinc, increasing in diameter from the eye to the object-end: the wide end of each zinc tube overlapping the narrow end of the following tube, and leaving an annular space of about an inch in width round the end of each for the purpose of ventilating the tube, and preventing, as much as possible, all interference by currents of warm air, with the cone of rays. The zinc tubes are also made to act as diaphragms.

The object-glass has an aperture of 25 inches (nearly), and in order as much as possible to avoid flexure from unequal pressure on the cell, it is made to rest upon three fixed points in its cell, and between each of these points are arranged three levers and counterpoises round a counter-cell, which act through the cell direct on to the glass, so that its weight in all positions is equally distributed among the 12 points of support, with a slight excess upon the three fixed ones. The focal length of the lens is 29 feet. A Barlow lens is arranged to slide on a brass framework within the tube. The hand is passed through an opening in the side of the tube, and by means of a handle attached to the cell, the lens may be pushed into or out of the cone of rays.

Attached to the eye-end of the tube are two finders, each 4 inches aperture; they are fixed above and below the eye-end of the main tube, so that one may be readily accessible in all positions of the instrument. It is also supplied with a telescope having an O. G. of 61". This is fixed between the two finders, and is for the purpose of assisting in the observations of comets and other objects for which the large instrument is not so suitable. This assistant telescope is provided with a rough position circle and micrometer eye-pieces, and is illuminated by new apparatus lately described in NATURE.

Two reading microscopes for the declination circle are brought down to the eye-end of the main tube; the circle -38 inches in diameter-is divided on its face, and read by means of the microscopes and prisms.

The slow motions in declination and R. A. are given by means of tangent screws, carrying grooved pulleys, over which pass endless cords brought to the eye-end.

The declination clamping handle is also at the eye-end. The clock for driving this monster telescope is in the upper part of the pillar, and is of comparatively small proportions, the instrument being so nicely counterpoised that a very slight power is required to be exerted by the clock, through the tangent screw, on the driving wheel (seven feet diameter), in order to give the necessary equatorial motion.

The declination axis is of peculiar construction, necessitated by the weight of the tubes and their fittings, and corresponding counterpoises on the other end, tending to cause flexure of the axis. This difficulty is entirely overcome by making the axis hollow, and passing a strong iron lever through it, having its fulcrum immediately over the bearing of the axis near the main tube, and acting upon a strong iron plate rigidly fixed as near the centre of the tube as possible, clear of the cone of rays. This lever, taking nearly the whole weight of the tubes, &c., off the axis, frees it from all liability to bend.

The weight of the polar axis on its upper bearing is relieved by friction rollers and weighted levers; the lower end of the axis is conical, and there is a corresponding conical surface on the lower end of the trough; between these two surfaces are three conical rollers carried by a loose or "live" ring, which adjust themselves to equalise the pressure.

The hour circle on the bottom of the polar axis is 26 inches in diameter, and is divided on the edge,* and read roughly from the floor by means of a small diagonal telescope attached to the pillar; a rough motion in R.A. by hand is also arranged for by a system of cog-wheels moved by a grooved wheel and endless cord at the lower end of the polar axis, so as to enable the observer to set the instrument roughly in R.A. by the aid of the diagonal telescope.

The declination and hour circles will probably be illuminated by means of Geissler tubes, and the dark and bright field illuminations for the micrometers will be effected by the same means.

Mr. Newall, after the preliminary testing of this magnificent instrument at his own residence, purposes to erect it in some climate favourable for astronomical observation. It is very unfortunate that this means in other words that the telescope cannot remain in England. It is or should be among the things generally known that every increase in the size of an object-glass or mirror increases the perturbating effects of the atmosphere, so that the larger the telescope, the purer must be the air. In the absence of this latter condition, a "big" telescope is a "big evil," and skilled observers, mindful of this, reduce the apertures of their instruments when the air is not good,

We may regard this telescope as a clear gain to English science, for Mr. Newall with princely liberality has expressed his intention of allowing observers with a special research on hand to have the use of the instrument during certain regulated hours.

The observatory, of which we also give a sketch, is nearly 50 feet in diameter, and notwithstanding the enormous weight of the dome, like the telescope, it is easily moved into any required position.

When complete it will have attached to it a transitroom and the observer's dwelling. And this reminds us that Mr. Marth, so well known for his good work done at Malta with the Lassell Reflector and elsewhere will have charge of this noble instrument of research.

NOTES

THE anniversary meeting of the Geological Society takes place to-morrow, when Professor Huxley will deliver his address, which, it is expected, will be of great scientific interest. The Wollaston Medal of the society has this year been awarded to the eminent French Malacologist, M. Deshayes, professor at the Musée d' Histoire Naturelle, and the proceeds of the Wollaston fund have been awarded to M. Marie Roualt, who, though in humble circumstances, has contributed largely to the advance of the paleontology of France. The choice of president for the coming year has fallen on Mr. J. Prestwich-a choice which will be hailed on all sides with the liveliest satisfaction.

IN reply to an address of last Session, Her Majesty has made known to the House of Commons that she will give directions for the carrying out of the arrangements necessary for observing the transit of Venus, which will take place in the year 1874

THE Rev. Charles Pritchard, of St. John's College, Cambridge, has been elected to the Savilian Professorship of Astronomy, as successor of the late Professor Donkin. Astronomers may con gratulate themselves on this appointment, as Mr. Pritchard's teaching powers are of the first order, the interest he takes in *The hour circle is also divided on its face, and read by micrometer microscopes.

the science is well-known, and his labours for its advance, especially in connection with the Royal Astronomical Society, have now extended over many years.

THE President of the Royal Society has sent out cards for two evening receptions, which are to be held at Burlington House on March 5, and April 23.

We understand that 75 towns have signified their intention of contributing to the fund required by the British Association Committee on the Treatment and Utilisation of Sewage, for the investigation of this subject, Manchester heading the list with a contribution of 100%.

At the ensuing meeting of the Geological Society on the 23rd inst., a paper of especial interest will be read, on the subject of copper mining at deep levels in the South of Ireland, experience having disproved the dictum of Irish geologists as to the nonexistence of metalliferous strata at any considerable depth.

THE number of candidates for election as members of the Royal Institution may, we hope, be taken as a fair indication of the daily increasing interest taken in scientific matters. The number elected last year was forty-seven. The number of candidates proposed during the first six weeks of the present year is forty-two.

M. NAUMANN has been elected a corresponding member of the mineralogical section of the Academy of Sciences in Paris, in the place of Sir Roderick Murchison, who has been made a foreign associate. He received 27 votes out of 44, of the remainder 10 being recorded in favour of our countryman, Professor Miller, and 5 for Professor Studer, of Berne.

AT the meeting of the Académie des Sciences, on the 31st of January, M. de la Roche Poncié was erected to the place rendered vacant in the Bureau des Longitudes by the death of M. Darondeau.

M. ALGLAVE announces in the Revue des Cours Scientifiques, that the total amount subscribed to the Sars Fund, is now up. wards of 160/., including the subscriptions of twenty-eight members of the Royal Belgian Academy, the same number of members of the Anthropological Society of Paris, M. Drouyn de Lhuys, and several members of the Zoological Society. We have the satisfaction to announce further subscriptions to the fund in this country, which appear in our advertising columns.

WE hear that the eminent geographer Kiepert is about to proceed to the Holy Land, and spend some time there, for the purpose of personally determining geographical positions. He has the advantage over our University explorers, recently sent out, in being a skilful and experienced geodetist, and of acquaintance with the country obtained during a former sojourn of several years. A COMMITTEE has been appointed to inquire into the education of naval officers, consisting of Rear-Admiral Shadwell, C.B., President; Captain W. H. Richards, R. N., Hydrographer, Captain A. A. Wood, R.N., Director of Naval Ordnance, the Rev. Dr. Woolley, Admiralty Director of Education, the Rev. A. Barry, D. D., Principal of King's College. S. P. Butler, Esq., Barrister-at-law, Richard Saintbill, Esq., R.N., Secretary.

PRIZES are offered by the Royal Belgian Academy for essays on the following subjects:-1. To give a résumé of and to simplify the theory of the integration of equations containing partial derivatives of the first two orders. 2. A study of electrical currents based as far as possible on new experiments. 3. To fix by new researches the place to be occupied in the natural system, by the species Lycopodium, Selaginella, Psilotum, Tmesipteris, and Phylloglossum. 4. To describe the mode of reproduction of eels. 5. New researches to establish the composition and mutual relations of albuminoid substances. The gold medal to be given for the first and fifth of these

questions is to be worth 40/., that for the second, third, and fourth questions, 24/. The essays must be written in Latin, French, or Flemish, and addressed paid to M. Ad. Quetelet, the Perpetual Secretary, before the 1st of June, 1871. The Academy will require the greatest exactness in the quotations, and the pages as well as the editions of works cited, must be given.

ANTHROPOLOGY is being publicly taught in Paris by one of the most distinguished masters of that science, Dr. Paul Broca. The conférences are held every Monday and Friday at 3 o'clock at the Anthropological Laboratory, No. 15, Rue de l'Ecole de Médecine. The instruction given has reference chiefly to craniology and the comparative anatomy of man and the apes. We also learn from Herr F. von Hauer that a new Anthropological Society has been formed at Vienna. It already numbers twenty-four members, among whom are several distinguished men of science. The society will publish a journal. In a prospectus which has been issued it is stated that the study of the natural history of man has now reached a stage in which active support by association appears to be imperatively needful. AT a recent meeting of the Zoological Society of London, Professor Owen communicated a very interesting letter, which he had lately received from Dr. Julius Haast, F.R.S., of Canterbury, New Zealand, on the subject of the extinction of the Moa, or Dinornis. Dr. Haast was of opinion that these gigantic birds had been extinct many hundreds of years, and had been so before the arrival of the Maories in New Zealand, having been exterminated by a race which previously inhabited these islands near the mouth of the river Rakaia. He had recently been so fortunate as to find the remains of a former large encampment of these "Moa hunters." The kitchen-middens and cooking-ovens, which were still completely preserved, were spread over more than forty acres in extent. Numerous stone weapons were discovered, consisting either of hard sandstone or of chipped flint. The Moa bones were very abundant, but belonged chiefly to the smaller species, Dinornis casniarinus, D. didiformis, and D. crassus. There were also some bones of D. elephantopus, and of a small Palapteryx ingens, but none of D. giganteus and D. robustus, The leg bones of these birds had all been broken at the ends, so as to allow the marrow to be extracted, and the skulls scooped out from below, so that the brain might be reached. The middens likewise contained bones of the domestic dog, sea-gull, and the tympanic bones of several species of whale, but no human remains had been found amongst the heaps, so that it might be presumed that the Moa-hunters were not cannibals.

PROFESSOR LIEBIG disputes Pasteur's view that the decomposition of sugar in fermentation, depends on the development and multiplication of yeast-cells and that fermentation generally is only a phenomenon accompanying the vital process of yeast. He expresses the opinion that Pasteur's researches have not explained fermentation; but have only made known another phenomenon the development of yeast-which equally requires explanation.

A NEW Flora of India by Dr. Hooker and Dr. Thomson is in preparation, and the first volume is expected in the course of the present season. This will supersede the old "Flora Indica " by the same authors, the first volume of which was published in 1855. The fifth volume of Mr. Bentham's "Flora Australiensis" is also announced as nearly ready.

AT the monthly session of the Imperial Geographical Society of Russia, held December 3rd, under the presidency of Count F. de Lütke, a memoir was read from M. Popow, of the Russian embassy, Pekin, on the "export of tea from Hankow," amounting to 50,000,000 lbs. -one-third of the total export from China-of which 15,000,000 is sent by twenty-eight Russian merchants. Among the measures adopted by the council in November was one concerning Mr. Hayward's expedition in Central Asia.

At the request of Sir Roderick Murchison, president of the Royal Geographical Society, London, the council sent a request to the Governor-General of Turkestan, that he would

welcome Mr. Hayward if he reached the Russian frontier. M. Ivaschintzew read a paper on the "eastern coast of the Caspian Sea, with reference to the commercial routes to Central Asia." The Volga, the only means of communication between the interior of Russia and the Caspian countries, presents great difficulties, there being only one channel available, the Western, which is navigable only by boats drawing four to five feet. The eastern coast of the Caspian is described as generally bare of any vege tation. From the Emba to the Atrek there are no springs; wells of brackish water are found, apparently the sea-water infiltrated. The north-east const is inaccessible: vessels cannot even approach within sight of the shore. Among the important points on the south-east shore are Sarytasch and Manghischlak coalfields, and the port Tubkaragan, the gulfs of Karabougaz and Balkan. The bay of Krassnovodsk-the occupation of which was recently announced-does not freeze in the winter; navigation, however, is reported by the Turcomans to be impeded for fifteen days by floating ice. The writer gave an account of the various explorations of Central Asia, including the attempts of the English from the sixteenth century, the expedition of Prince Békovitch, the attempt of Voiniovitch to establish commercial relations at Astrabad in 1781. The new routes to Central Asia from the centre of Russia are superior to the old, as avoiding the Kirghiz-steppe. The necessity was shown of interesting the Turcomans and the inhabitants of Khiva in commerce, and of making accurate surveys of the country between the Caspian and the Amu-Daria. THE Academy states that M. Leon de Rosny, Professor of Oriental languages at the Imperial College, has published a French translation of a Japanese treatise on the rearing of silkworms. This work is published "par orde de son Excellence le Ministre de l'Agriculture." It is the first French translation of a Japanese work.

THE Lancet in speaking of the arrangements of hospitals, instances, as much needing reform, the system of grouping together indiscriminately in medical wards, cases of various affections, in an atmosphere which may be destructive to some patients while it is suitable to others. Thus we may find lying side by side a case of bronchitis and one of fever; a patient with phthisis and another with gangrene of the lung; next perhaps one of rheumatic fever closely adjacent to a paralytic with offensive bed

sores.

THE Royal Irish Academy has voted the sum of 257. to Professor King, to enable him to carry out his researches "on the jointing. foliation and cleavage of rocks," also the same amount to Professor Ball, to enable him to carry out his experiments "on the velocity of smoke rings in air."

A NEW instance of the earnestness and liberality with which the King of Prussia encourages the prosecution of geographical discovery, has been communicated to us. The enterprising traveller, Gerhard Rohlfs, receiving kindness from the ruler of Kuka, he promised that presents should be sent from the King of Prussia, and Herr Nightingale is now on his way as the bearer of the presents. Poor Miss Tinne's death having proved the danger of the way beyond Mursuk, the Prussian Government has consented to send a guard of fifty soldiers (volunteers for the duty) to escort him in safety through the Touaregs to Kuka.

THE Academy reports that Herr O. Liebreich has found chloral may be employed with good results as a counteractive to poisoning by strychnine. On the other hand, the evil effects of an overdose of chloral may be remedied by the use of strychnine. M. GORSEIX states in a letter, communicated to the Academy of Sciences, by M. St. Claire Deville, that Santorin was still in active eruption on the 6th of last month.

MAGNETIC AND SUN SPOT PHEΝΟΜΕΝΑ FOR 1870

APPEARANCES would indicate that we are now the disturbances of terrestrial magnetism and also as approaching the epoch of maximum, both as regards regards solar disturbances or sun spots; for these interesting phenomena are believed to march together. There is still a third phenomenon intimately connected with magnetic disturbances, and that is, the Aurora Borealis, a meteor which seems to sympathise with the terrestrial magnetic system to such an extent that when this is fluctuating and disturbed, displays of the Aurora are almost sure to follow.

Finally, those of us who are of an intensely practical turn of mind will be delighted to know that this interesting chain of facts is bound by one of its links, if not by two, to the practicalities of everyday life. For, in the first place, displays of the Aurora are hardly ever unaccompanied by spontaneous currents making their appearance in telegraphic wires, and causing not a little confusion in the transmission of messages; and, in the next place, some mineralogists are of opinion that these very currents are connected in some way with metalliferous deposits.

Perhaps, after all, the relation between sun spots and California may be that of cause and effect !

The first great magnetic disturbance recorded at Kew Observatory, during the last month, began about 7 a.m. on January 3, by considerably and abruptly diminishing the declination and the horizontal force, without greatly affecting the vertical force. It lasted for about 16 or 17 hours, and during its continuance an Aurora was visible.

A smaller disturbance began on January 8, about 9p.m., its tendency being to diminish the declination and the vertical force, without much affecting the horizontal force: it was likewise accompanied by an Aurora.

The solar disc was photographed at Kew Observatory nine times during the month of January, with an average of five groups of spots on the sun's surface, one of them being always large. Thus we have :

Moniteur Scientifique, February 1.-In this number M. Emile Kopp gives an account of Weldon's well-known process for the regeneration of "manganese." In a note on the Infinitesimal Calculus, M. Néhay maintains that neither the infinitely great nor the infinitely small can be considered as real quantities; that the algebraical relations established in the calculus for such quantities depend solely on the conservation of certain ratios and not on any particular unit, and are hence true for magnitudes as great or as small as we please; and that infinitesimals can alway be exchanged for finite proportionals. Bolley finds on analysis that the artificial alizarine of Meister, Lucius, and Co. has very exactly the formula C1H8O4.

14

Revue des Cours Scientifiques, February 12.-This number contains a long list of subscribers to the Sars Fund; a report by M. Cazalis de Fondouce, of the proceedings of the Anthropological Congress at Copenhagen; also a lecture delivered at the Faculte de Médecine at Paris, by M. Onimus, on the balanced forces (Forces en tension) and active forces (forces vives) in the animal organism.