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Pros. Cope obtained five adult and two half-grown individuals, then A is listed out, leaving a vacancy equal to its volume. The and had two other adults almost within his grasp, but they vessel V is now put into one scale of a hydrostatic balance, and escaped him. The specimens agree nearly in size, the chief the body A hung under it ; then weights are put into the other differences being observed in the amount of dark blotching of scale till equilibrium occurs. If now the balance is lowered the belly and the regularity of the markings on the inferior side till A dips wholly in the water of a lower vessel V', the disturbed of the femur. The specimens were found in a “cut-off” of a equilibrium can be restored by simply filling up the vessel V tributary of the Great Egg Harbour River, in Atlantic county, with water. New Jersey. The water is stagnant, and is well grown with Nymphæas, Utricularia, and Sphagnum. The frogs did not

It has been long known that glass is attacked and dissolved display any considerable powers of leaping or swimming, but

in small quantities by ordinary water. This dissolving process concealed themselves with much ease within the aquatic vegeta- | Herr Pfeiffer has recently sought to prove and measure by tion. Prof. Cope did not observe any voice. In the same change in the electric conductivity of the water (Ann, der locality he observed the Ranæ virescens and clamata. The Physik). He measured the increase of conductivity undergone “cut-off” is in the woods, and he found no individuals in by i cubic centimetre of pure water when it has been in consimilar situations in the open country, nor any along running

tact for one hour with one square centimetre of glass surface, water in the woods. The oversight of this conspicuous species,

and concluded that the amount of glass dissolved at 20° C. was as Prof. Cope says, is a curious circumstance.

I to 2 millionths of a milligram. He found, too, that with

temperature rising arithmetically, the growth of solubility is ACCORDING to a statement in the Toronto Monetary Times, considerably more rapid than that of a geometrical series ; that grape-culture is becoming an important industry in Ontario. the increase of conductivity of the water for a given kind of glass The centre of the vine cultivation is between Grimsby and under like conditions is a characteristic constant ; and that later, St. Catharines. In Essex, especially on Pelee Island, experience when a certain quantity of alkali is dissolved, further action has shown that grapes can be profitably grown.

Some local ex.

involves a dissolving also of silicic acid, and the salts then periments show a probability that in the near future the county formed may cause a decrease of conducting power. of Norfolk will be added to the vine land of the province. The quality of the grapes grown has of late been greatly im- BARON NORDENSKIÖLD communicated to the December proved, and so prolific are the vines that growers have this meeting of the Royal Swedish Academy of Science the fact that season in many instances had to be content to take one and a he has discovered notable quantities of uranium in the asphaltic half cents a pound for good samples. Grape culture is rapidly or rather anthracitic minerals, accompanying the magnetic and extending, especially in the county of Welland. This year's hæmatite iron ores in Sweden. A large block of so-called price for grapes is perhaps about as low as they can be grown at “anthracite” from Norberg, for instance, leaves, when burned, a profit, but it looks as if the supply might in future outstrip the ashes (13 per cent.) which contain about 6 per cent. of uranium ; demand.

a similar mineral from Dannemora left, when burned, ashes con

taining 4 per cent. of uranium. The Norberg mineral also conIn the report on his work during 1890, lately issued, Mr. R.

tains cerite anil gadolinite oxides, although in small quantities, L. Jack, the Government Geologist of Queensland, refers to a

and it is remarkable that the mixture of gadolinite oxide (yttria, collection of geological specimens forwarded by the Administrator of the Government of British New Guinea. The collec- ytterbia, &c.) from this new provenance has the normal atomic

weight of 25546 (for R,O3). tion demonstrated (1) the presence of gold, topaz, and beryl in the bed of the Fly River ; (2) the presence, within the drainage TETRA-IODIDE of carbon, CI., has been obtained in large area of the river, of (a) stratified rocks in an unaltered condition,

ruby red crystals by M. Moissan by the action of his recentlyincluding sandstones, clays, limestones, and lignites ; (6) meta- prepared boron iodide, Big, upon carbon tetrachloride. Boron morphosed stratified rocks, including slates and greywackes ; iodide is a substance crystallizing from solution in carbon biand plutonic and igneous rocks. A number of concretionary sulphide in colourless tabular crystals which melt at 43° to a ironstone nodules probably indicated the presence of metalliserous liquid boiling at 210". It is a substance of great chemical lodes. Some fossil corals, in limestone pebbles probably of activity, reacting with considerable energy with a large number Mesozoic age, from the first and second rapids of the Fly River, of substances, as described in NATURE, vol. xliii. p. 568. When have been sent for identification to Mr. Robert Etheridge,

it is brought in contact with carbon tetrachloride, double dePaläontologist to the Geological Survey of New South Wales

composition occurs in the cold, with a large evolution of heat and the Australian Museum. A second collection of rocks from

boron chloride and carbon tetra-iodide being formed. Toulon Isle, Port Hennessy, Red Point, Teste Isle, Rossel Isle, &c., was examined by Mr. Maitland. Among these were

4B13 + 3CC1, = 4BC12 + 3CI.. grits, sandstones, sbales, limestones, basalts, granites, and quartz The best mode of operating is to heat the two substances, the containing a minute quantity of gold.

crystals of boron iodide and excess of dry redistilled carbon

tetrachloride, in a sealed tube for one hour at a temperature of M. CARTAILHAC contributes to the current number of 80°-90°. Next morning the tube is found to contain large L'Anthropologie an excellent abstract of an elaborate paper by crystals of carbon tetra-iodide, which appears to be produced in A. J. Evans on a late Celtic urn-field at Aylesford, Kent. Other

theoretical quantity. After opening the tube, the crystals are contributions are a fresh instalment of T. Volkov's interesting drained, washed with a solution of bisulphite of soda in order to account of marriage rites and usages in Ukraine ; a paper by E. remove the last traces of iodine, and finally dried in vacuo. T. Hamy on the country of the troglodytes ; and an essay, also When the red crystals thus obtained are heated to 100° in an by E. T. Hamy, on the ethnographical work of Nicolas-Martin

exhausted sealed tube, they slowly sublime into the colder porPetit.

tion of the tube in magnificent brilliant red crystals very much FOR experimental proof of the principle of Archimedes, M.

resembling the artificial rubies prepared by MM. Fremy and Paquet Journ. de Phys.) recommends the following general

Verneuil. The reactions of carbon tetra-iodide are somewhat method : Into any vessel, V, is brought the body A (which is the

interesting. When heated in a current of hydrogen at a temobject of experiment), with attached wire by which it can be

perature about 140°, it is reduced to iodoform, CHIg. conveniently hung. The vessel is then filled up with water ;

CI, + H2 =CHI, + HI.

When the crystals are placed in an atmosphere of chlorine they latitudes simultaneously determined by zenith telescope observaat once liquefy, and the liquid becomes hot. The products are

tions of the same pairs of stars. "An annual motion of the carbon tetrachloride and liquid chloride of iodine, ICI, which

Pole of o" '045 will alter the difference of latitude of these

stations by twice this amount per year, giving a change in latter gradually volatilizes away in the form of the chloride, IClz.

the difference of latitude amounting to 1" in eleven years-a CI, + 4C1, = CCIA + 4ICI.

quantity which cannot possibly escape careful observation with

the zenith telescope or prime vertical transit. If similar obserWhen heated gently in dry oxygen, it becomes decomposed vations be made 20° east of Greenwich, they will furnish the into iodine and carbon, which latter burns away to carbon best obtainable data for determining the direction of motion of dioxide upon slightly raising the temperature. Melted sulphur the Pole." All sources of systematic error can be eliminated reacts with carbon tetra-iodide with considerable violence ; by the adoption of such a method, and our knowledge of secular vapour of iodine is evolved, carbon deposited, and iodide of astronomer, will be of a more definite character than at present.

variations of latitude, as important to the geologist as to the sulphur formed. If, however, powdered sulphur is warmed

THE ROTATION OF VENUS.-Herr Löschardt sends us a with carbon tetra-iodide to 50°, iodide of sulphur and carbon bi

paper on Schiaparelli's hypothesis as to the period of rotation of sulphide are produced. Phosphorus acts with great energy upon Venus, presented by him to the Vienna Academy of Sciences it, forming compounds which are still undergoing investigation. on March 12, 1891. He criticizes the conclusions drawn by Sodium and potassium react with incandescence, an alkaline Schiaparelli from observations made by others and himself, and iodide and free carbon being produced. Mercury and silver points out that the observations made by Denning in 1881 favour likewise attack it at the ordinary temperature, and very rapidly days. Herr Löschardt has made a number of drawings of the

the old rotation period of 23d. 21m. rather than one of 224 upon warming. Warm hydrochloric and hydriodic acids attack

markings on the planet shown by his 3-inch resractor at Nákóthe crystals rapidly, with formation of iodoform and liberation of falva, and the discussion of them gives support, on the whole, vapour of iodine. A particularly interesting reaction is that to Cassini's value of the rotation period. The chief reasons with fluoride of silver. When a quantity of this salt is placed which led to this conclusion are the differences between Perin a solution of carbon tetra-iodide in carbon tetrachloride

rotin's observations and those made at Nákófalva at different

hours in the same day, the circular form of polar patches, and warmed to 50°, a regular evolution of gaseous carbon tetra

the ellipsoidal distribution of the atmosphere, which is said to be fluoride occurs.

the result of swist rotation. CIA + 4AgF = CI 4Agl.

STARS HAVING PECULIAR SPECTRA.-In a communication This reaction affords the readiest means yet discovered of pre- to Astronomische Nachrichten, No. 3070, Prof. Pickering reparing carbon tetrafluoride.

cords that the three stars tabulated below show bright lines in

their photographic spectra, and belong to the same class as the The additions to the Zoological Society's Gardens during the stars discovered by Wolf and Rayet :past week include a Vervet Monkey (Cercopithecus lalandii ) Designation.

Galactic Galactic

longitude. from South Africa, presented by Mr. J. Parr; a Bonnet Monkey (Macacus sinicus 8 ) from India, presented by the Rev. W. P.

D.M. + 55-2721

55 37 -0 50

70 29 Beckett; a Black-faced Kangaroo (Macropus melanops 9 ) from

55 46

71 38

D.M. + 56.2818 Australia, presented by Mr. P. Clark; two Red-crested Finches

22 329

-- I 25

73 3 (Coryphosphingus cristatus) from South America, presented by It will be seen that these stars, like the 35 others of the same Commander W. M. Latham, R.N., F.Z.S.

class, sall near the central line of the Milky Way.

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R.A. 1900.

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22 15'0
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THE TOWER OF BABEL AND THE OUR ASTRONOMICAL COLUMN.

CONFUSION OF TONGUES.1 Journal of Science for December contains a paper on secular right angles, its quays along the banks of the Euphrates, its

THE SECULAR Variation of LATITUDES. – The American WHO among the readers of ancient history has not pictured variations of latitudes, read by Prof. George C. Comstock at the Washington meeting of the American Association for the royal palaces, its double walls, and last, not least, its towers in Advancement of Science. The determinations of the latitude stages, dedicated to the various gods? The picture of grandeur of Greenwich made from the time of Flamsteed (1693) to now

is one of which we can form an estimate only, but it must have that is, over a period of very nearly two centuries-indicate a

been magnificent beyond what was customary in those days, for very appreciable progressive diminution. But as the observa

had not the great Nebuchadnezzar built it? He describes at tions were made with five different instruments, and are affected, great length what he had done for the city, for its walls, for its to an uncertain extent, by various sources of error, no definite streets, its temples, its towers, and its palaces. conclusion can be drawn from them. In the cases of the lati

But there was a time when Babylon was not the great city. tudes of Pulkowa, Königsberg, Washington, and Madison,

At first a village settlement, it gradually arose to be the capital however, Prof. Comstock thinks there is definite evidence of of a powerful State, a progress that probably occupied 4000 a change of latitude, and from an examination of numerous

years, not including the pre-historical period. "The story of the absolute observations, and a reduction of recorded star-places, beginnings of this great city, which are lost in antiquity, is told he arrives at the data contained in the following table :

in Genesis, and forms one of the most charming of the legends

of the Bible. The Biblical account is given in the geneaLongitude

Annual

Computed logical table just before "the generations of Shem,” and seems Station. (from Variation

to be an interpolation to explain the numerous languages of the Greenwich). of Latitude.

Variation.

world. What the source of the legend may be is uncertain, but Pulkowa

- 0:006

- 0'007

as a whole it is unique, for though its source is possibly BabyKönigsberg ...

- 0.003

lonian, nothing like it has yet come from that country or from Washington

+ 0'042

+ 0*044

Assyria. The so-called Babylonian legend of the Tower of Madison 89'4 W.

+ 0'043

+ 0.041

Babel seems to have nothing to do with the Biblical one

indeed, ihe evidence all points to its referring to something A least square solution of the observed data was made to entirely different. determine the most probable direction and amount of motion “As they journeyed (so the Bible narrative says) in the East, of the Pole. The result was o" 044 along the meridian 69° W. they found a plain in the land of Shinar.” This land of Shinar of Greenwich. The values contained in the last column of the is generally regarded as the Sumer of the Babylonian and above table were computed from these elements. For the sys- Assyrian inscriptions. The Sumerians and Akkadians were of tematic investigation of the motion of the Pole it is suggesied a different stock from the Semitic inhabitants of the country, and that two stations in about the same latitude, but having longi.

Abstract of a Lecture by Theo. G. Pinches, before the London Intudes about 70° W. and 110° E. respectively, should have their stitution, December 3, 1891.

Annual

30'3 E. 20'5 E. 770 W.

- O'000

spoke two entirely different dialects, making, with the Kassite,

At È-bara, the seat of thy lordship,

Show forth thy supremacy. the Semitic Babylonian, the Aramaic, and the Chaldee, no less

May Aa, thy beloved wife, than six dialects and languages; and, as if this Babel were not

Gladly go to meet thee. enough, the tones of Elamites and other foreigners might also

May thy heart take rest, be heard. It will probably be admitted that ihe consusion of

May the property of thy godhood

Be confirmed to thee. tongues which this gathering of nations made at Babylon was

Warrior, hero, Sun-god, may they glorify thee ! striking enough to the visitor in whose native land one language only prevailed.

Lord of É-bara, may the road of thy path be prosperous

Sun-god, cause thy highway to prosper, The indications point to the fact that the Akkadians were the

Going the everlasting road to thy rest. invaders in Babylonia, and they gave a great many kings to the

Sun-god, thou art he who is the judge of the land, land. It was a state of things not unlike the heptarchy in Old

Causing her decisions to be prosperous. England-a num her of small States fighting amongst themselves, The priests' morning hymn began :the most powersul gradually absorbing the weaker, until, about

“Sun-god, in the glorious heavens rising,” the time of the great Hammu-rabi, about 2220 B, C., the whole became united ; after which date probably only the wild and the lecturer pictured the day when the priests who chanted Chaldæan tribes remained practically independent, under their these hymns were there no more, and the faith which had raised native chiefs, and afterwards gave kings 10 Babylonia itself. Babylon's splendid temples and noble towers was, at last, as

The Semitic Babylonians of Mesopotamia were probably rather dead as her departed glories, to become the heritage of short and thick-set, though there must have been a great many

the student and of those who love to hear the ever-charming people of normal height and even iall stature among them. stury of the romanceful East. They were dark and heavily bearded, hut during the time of the Akkadian supremacy they seem to have shaved, like their rulers. The Akkadians seem to have had noble and dignified features,

A YEAR'S SCIENTIFIC WORK IN NEW and their figures, as shown on the engraved and sculptured

GUINEA. stones, were far from inelegant. The e was also, apparently, a type of Akkadian with a curved prominent nose and a retreat A RECENT administration report from New Guinea, issued ing forehead, something like the Elamites shown on

by the Colonial Office, contains an appendix on the Assyrian bas-reliefs. [Several examples of the various types scientific work of the year in the island.

The first paper were shown.)

in this is a report by Baron von Mueller on the botanical These people, journeying "in the East,” resolved to build a specimens collected He says that the increase in our city “and a tower”; and this tower, which the inhabitants of knowledge of the Papuan Aora, derived from Sir William Shinar decided to build, was quite a special thing of their own. MacGregor's collection in 1890, has been again important. Every city in ancient Babylonia had a tower, some more than Foremost as a result we learn from these contributions that one, and they were of varying forms. The Semitic Babylonians a considerable number of Australian species of plants, which, seem to have called their memorial towers zikkurāti, a name as such, were hitherto regarded as quite endemic, are likewhich was even applied (as in the Babylonian account of the wise indigenous to the vicinity of the Mai-Kussa and Wasi. Flood) to natural eminences of a similar form. The Akkadians Kussa in New Guinea. Thus they occur precisely opposite appear to have called them “watch-towers.” They were in- to Cape York, from whence the seeds may have been tended (according to Perrot and Chipiez) to give that picturesque carried' across by migratory birds or perhaps by some other element to the land which accidents of Nature usually give to agencies. These, otherwise only Australian, plants may thereother countries more favoured, and also to astonish the contem- fore not really belong to the primitive vegetation of New Guinea, porary traveller, as well as that posterity for whom no more though they are now established in such a way as not to admit than a heap of shapeless ruins would remain. However that of distinguishing them in regard to their origin from the great may be, they certainly served in their time a practical purpose- bulk of the lowland species, whether truly Papuan or simultanamely, for religious ceremonies, and for astrological and astro- neously also Malayan. The occurrence has already been nomical observations. There were twenty-two principal erec- demonstrated of a number of lowland plants of specific Austrations of this kind in the earliest period in Babylonia, according lian type in various parts of New Guinea. To ihese can now to one of the lists.

be added a number of others which are specified by Baron Descriptions and illustrations were now given of the different von Mueller. It can now be shown also that the cedar (or forms of towers in Babylonia, and it was pointed out that rather cedrel), of which many shipments have been made to Nebuchadnezzar mentioned a' " Tower of Babel” (zikurat Australian ports, is identical with ihe Singapore cedar (Cedrela Babilan) which he "made anew," and "raised its head with Toona). The magnificent and renowned aquatic plant, Nelumbo burnt brick and bright lapis" ; but he did not devote many words nucifera, has now been located on the upper Fly River. Some to it--why, is not known, unless it be that some ill omen was other planıs, unh nown from New Guinea before, such as attached to it. This “Tower of Babel" of Nebuchadnezzar is Polygala chinensis, Salomonia oblongifolia, Sesuvium Portulanot the Birs. Vimroud, and for that reason, as well as because the castrum, Leptospermum Javanicum, and Limnophila gratio. latter did not lie within Babylon, we may doubt whether it beloides, are recorded in the Administrator's last collection, while the Biblical “Tower of Babel," as has been, and still is, some more are awaiting careful comparative elucidation belore supposed.

the fixing of their systematic position. Count Solms-Laubach, Ii is difficult now to imagine the place where the great con- the monographer of Pandaneæ, has acknowledged the screw fusion of tongues existed as the site of a great city, with its pine from Ferguson Island, in the Louisiades, as a new species teeming life. The place where Babylon stood is now a series under the name P. Macgregorii. An essay of Baron von of mounds more or less shapeless, and masses of brickwork, but Mueller on the highland plants collected during the year by otherwise a marsh. The“.

'great city, “the beauty of the Sir William MacGregor has appeared in the publications of the Chaldees' excellency,” has “become heaps.” The ruins of the Royal Society of Victoria. But he was able to examine only a palace of Nebuchadnezzar, and of the temple-tower of Babil, few of the ferns brought from the upper region of the Owen are among the more prominent remains.

Stanley Range ; among them, however, is the new Cyathea After a sketch of the life of the city of Babylon in ancient Macgregorii

, which reaches a higher elevation than any other times and the religious festivals and ceremonies, and how the of the many kinds of fern-trees now known. To expedite the temple-towers and the services remained after the cities had determination of their specific position, Mr. Baker, of Kew, has decayed and practically vanished, the lecturer recited a transla. undertaken to define systematically the seventy species of Ficilis tion of the hymn to the setting sun sung by the priests of Ê-zida, and Lycopodiacea, contained in Sir William MacGregor's colthe supposed Tower of Babel

lection from the Owen Stanley Ranges. Mr. Baker regards

nineteen of these ferns as new, and therefore, so far as our Hymn to the Setting Sun, chanted ly the Priests of È-zida. present experience reaches, as exclusively Papuan. These " Sun-god, in the midst of heaven,

hitherto unknown species are comprised within the genera Al thy setting,

Cyathea, Hymenophyllum, Dicksonia, Davallia, Lindsaya, Aspi-
May the latch of the glorious heavens
Speak thee peace;

dium, and largely Folypodium. The Curator of the Queensland May heaven's door to thee be gracious;

Museum reports on the zoological collections. No new animal May the Director, thy beloved messenger, direct :hee,

of the warm-blooded class has been met with during the year ; perhaps those remaining to be found in the coast country are

SCIENTIFIC SERIALS. both few and rare. By way of compensation, however, certain Australian birds, the native companion, white ibis, and royal American Journal of Science, December.-On Percival's map spoonbill, must now be included in the Papuan avisauna as at of the Jura-Trias trap-belis of Central Connecticut, with obser: least temporary sojourners on the banks of the Fly River. It is

vations on the up.turning, or_mountain-making disturbance, noteworthy that these birds were found on the Fly River during of the formation, by James D. Dana. - The detection and the continuance in the north of Queensland of a drought which determination of potassium spectroscopically, by F. A. Gooch had driven them from their haunts proper and scattered them and T. S. Hart. By dipping platinum coils of different sizes far and wide in search of water. of the reptiles, on the other in a solution of the salt to be tested it was found possible to take hand, a few new forms are distinguishable. These occur among up known quantities of material for introduction into the the lizards. Two handsome snakes, Chondropython azureus volatilizing fame employed. Experimenting in this manner and pulcher, have been added to the State collection of Papuan with a single-prism spectroscope, it was found that to of a ophidians. On the whole, the vertebrate collection is subordi- milligram of potassium produced a line distinctly visible with a nate in importance and interest to that of the insect division slit of oʻ18 mm., and i'o mgr. with a slit of 0'23 mm. The of the invertebrates. The whole of the insects collected were test appears to be less delicate with potassium sulphate than examined by the Entomological Department, and two reports on when the chloride is used, and rather more delicate in the case the Lepidoptera and Coleoptera are appended. From these it of the carbonate. The red line of potassium was unmistakably appears that several species both of butterflies and beetles are

seen when only zdou mgr. of potassium was introduced into new to science. The collection contains in many instances a the flame in the form of the carbonate. For quantitative deterlarge series of examples of the same insect, which is all-important minations a standard solution, from which yto mgr. of potassium in the case of variable forms, whose unknown range of variation was taken by a certain platinum coil, was employed. The modus is a prolific source of error. Besides Lepidoptera and Coleoptera operandi was to dilute the test-solution until the line given by it contains many Hemipterous insects which have not yet been the potassium contained in a coil-full was of the same brightness determined. The few forms of Mollusca procured on the Fly as that given by the same quantity of the standard solution. River have yielded but one new species, a remarkably fine Remarkably consistent results were thus obtained. An interestNanina.

ing point brought out by the experiments is that the presence of

sodium salts in the fame is of direct influence in strengthening A MEDIUM FOR PRESERVING THE COLOURS solar prominences, by George E. Hale.

the spectrum of potassium,—The ultra-violet spectrum of the

This important paper OF FISH AND OTHER ANIMALS.

was read at the last meeting of the British Association, and has OUR readers may remember that Mr. Haly, Curator of the

been previously noted.-Phonics of auditoriums, by Ephraim Colombo Museum, has for some years been making ex

Cutter. It is generally known that a well-constructed auditoperiments so as to discover a medium which will preserve the

rium resonates certain sounds better than others, and that many colours of fish and other animals. We quote the following clergymen accommodate their tone of speaking to the key-note from the last Annual Report of the Colombo Museum :

of their church. Dr. Cutter has made observations on this “In my last year's report I made some remarks on the use of point in four halls, and recommends those who control carbolized oil as a mounting fluid for specimens already pre auditoriums to find the key.note and post up the result. Thus, pared by other means, the idea that it was a preservative in an auditorinm at Saratoga Springs was tested in 1890, and a itself not having occurred to me. Further experiments this year

notice was put up;

“The key-note of this hall is F."seem to show (I do not like to speak 100 confidently in a climate

The secular variation of latitude, by George C. Comstock. like this, even with twelve months' experience) that it is one of This is a general account of the observations made at the most perfect preservatives known both for form and colour. Greenwich, Pulkowa, Madison, and elsewhere, which indicate Coco-nut oil and carbolic acid freely mix in all proportions.

that the latitude of a single place is subject to a secular variaThe mixtures at present under trial are oil raised to the specific tion.-On the capture of comets by planets, especially their gravity of 10° and 20° below proof-spirit by the addition of acid. capture by Jupiter, by H. A. Newton. -Distribution of Whilst the gum and glycerine process is absolutely useless for

titanic oxide upon the surface of the earth, by F. P. Dunany animals except certain families of fish, this mixture is good nington, An estimation has been made of the titanium in for every kind of vertebrate. The most delicate frogs are quite eighty different specimens of soil taken from different parts of uninjured by it, and snakes undergo no change. The delicate

the earth's surface. Soils from Virginia gave an average of plum-like bloom on the geckoes, the sugitive reddish tint on 1'57 per cent. of titanic oxide, and twenty-two samples from such snakes as Ablabes humberti, are beautifully preserved by it.

other portions of the United States gave an average of Another most important use is in the preservation of large 0-85 per cent. The average proportion in air-dried soils from fish skins, which can be packed away in it for an indefinite

Oceania and Asia (14 -pecimens) was o'90 per cent., and period, and mounted when wanted. These skins do not require

16 specimens from Europe gave 0:54 per cent.

The eight varnishing, neither do they turn brown, but although, of course,

remaining estimations were made on typical rocks of the they do not preserve their sheen like fish in the oil itself, they localities which furnished the samples for analysis.--Notes on always maintain a silvery and natural appearance, quite different a Missouri barite, by C. Luedeking and H. A. Wheeler.—The from that of ordinary museum specimens. If ever we get a new

contraction of molten rock, by C. Barus. A sample of diabase fish gallery, a show of our large species prepared in this way

has been fused and allowed to cool slowly. The molten rock would form a most effective exhibition.

contracted regularly until a temperature of 1093° was reached, It appears also to be a most excellent preservative for

when the diabase solidified with a sudden contraction of bulk. Crustacea and the higher orders of Arachnids, and also for

The density of the original rock was 3.0178, and that of the Centipedes, but it has hitherto proved a failure for marine glass obtained 2717. The observations indicate that "strucinveriebrates in general. It must be remembered, however,

tural rock texture is due to pressure, i.e. pressure induces that the perfect miscibility of the two liquids opens up endless

a redistribution of molecules, such that the smallest specific possibilities: Its absolutely unevaporable nature makes it

volume possible under the given conditions may result."-Notes invaluable in a tropical climate, quite apart from its other

on Michigan minerals, by A. C. Lane, H. F. Keller, and F. F. qualities.

Sharpless. The minerals considered are chloritoid, grünerite, "With regard to this last remark I take the opportunity of and riebeckite. stating that the acid enables coco-nut oil and turpentine to be mixed together. This forms a splendid microscopic fluid, in which objects may be allowed to soak without any previous preparation, and in which they become very transparent. A

SOCIETIES AND ACADEMIES. minute species of Crustacean, of the order Copepoda, and the

LONDON. leg of a fly, simply laid on a slide in a drop of this fluid and covered with an ordinary covering-glass, without any cell being Royal Society, December 10.-"On a Compensated Airmade or cement employed, have lain on my table unaltered for thermometer.” By H. L. Callendar, M.A. the last ten months, and I cannot help thinking that such a The air-Thermometer is the ultimate standard to which all medium as this cannot fail to prove a great boon to all workers measurements of temperature have to be referred. It therefore with the microscope."

becomes a question of considerable importance to determine

what form of instrument is capable of giving the most accurate thermometers. They can be made with a range from 300°– results.

500° C. (500°-900° F.), and will read to a tenth of a degree at For practical purposes there can be no doubt that electrical 450° C. They are practically free from change of zero, and if resistance thermometers, which are much easier to read and properly compensated their indications are very reliable. Since manipalate, and which are, at the salue time, exceedingly con- the connecting tubes are compensated, they can be made of constant over a very wide range, would be much more convenient siderable length, and even of flexible material, such as compo. as standard instruments. But for theoretical work it is always tubing, without much loss of accuraey. This is often a matter necessary to reduce their indications to the scale of absolute of great convenience, especially in high temperature work. temperature.

With this object the writer has been for some years engaged “ Repulsion and Rotation produced by Alternating Electric in endeavouring to construct an air-thermometer which should Currents.” By G. T. Walker, B.A., B.Sc., Fellow of Trinity he capable of reading to a degree of accuracy comparable with College, Cambridge. Communicated by Prof. J. J. Thomson. that attained by the use of electrical-resistance thermometers. The author described the following experiment :-A sheet of This he believes that he has at length succeeded in securing by copper is placed so as to half cover an alternating magnetic she adoption of the modified and compensated form of differ- pole. Upon this, near the pole, is laid a hollow sphere of ential air-thermometer described in the paper.

copper,

The electro-magnetic action produces a couple so The common and familiar form of differential air-thermometer powerful that the friction of rotation is overcome, and the consists essentially of two equal bulbs, communicating with sphere spun round. opposite limbs of a U-tube of small bore containing sulphuric

In order to throw light on this, after a theorem in $ 2 as to the acid, which serves to indicate the difference of pressure between kind of currents set up in a conductor, I have considered a them. If the standard bulb be kept in melting ice, so that its number of cases. A thin circular infinite cylindrical shell lies temperature is constant, it is possible, by using a kathetometer in an alternating field of currents parallel to its axis, and the microscope, to read small changes of temperature in the thermo- couple upon it is found. The result is applied to give the metric bulb with an accuracy of the order of a thousandth of a couples on two such shells in the presence of a parallel current degree.

and of a pair of currents forming an electro-magnet. In order to make the instrument capable of reading over a The couple in action upon a thin spherical shell in a general wider range, it is only necessary to add an auxiliary buih, as in periodic field has next been found, and is applied to give the the ordinary "constant-pressure” type of air-thermometer, into couples on two thin shells under the influence of which the air from the thermometric bulb is allowed to dilate. (i.) An alternating current in a straight infinite wire. The auxiliary bulb is provided with taps, through which mercury (ii.) A pair of such currents forming an electro-magnet. can be introduced or withdrawn in weighed quantities, to equalize (iii.) An alternating magnetic pole. the pressures. The dilatation of the air at constant pressure (iv.) An alternating electro-magnet of very

short length. can be very accurately measured by weighing the mercury displaced. This form of air-thermometer has the advantage of Chemical Society, November 19,-Sir Henry Roscoe, being entirely independent of barometric readings. A great | F.R.S., in the chair. --The following paper was read :--Iron deal of trouble is thus saved ; moreover, it is certain that a much carbonyl, by L. Mond, F.R.S., and Dr. Langer. An account greater degree of accuracy can be attained in this way in the of this paper has already appeared in Nature of November 26 measurement of a volume than in the measurement of a pressure (p. 89).

A lecture was then delivered on colour photometry, by means of a mercury manometer, as in the " constant-volume” by Captain Abney, C.B., F.R.S. According to the lecturer, type of air-thermometer.

the colour of a body, when viewed in a light of standard With almost every form of air-thermometer, some part of the quality, is known when (a) its luminosity, (6) its hue, and (c) air contained in the connecting tubes is necessarily exposed to its purity, or the extent to which it is freed from admixture with temperatures different from those of the bulbs. In accurate

white light, are known and expressed by numbers. The work a correction must always be applied for this by calibrating luminosity of a colour can be given in absolute number by the connecting tubes and estimating their mean temperature. referring it to the standard of white. The standard of white This correction, however, is exceedingly troublesome to apply, employed is a surface coated with zinc oxide. It is also necessary and becomes a very serious source of uncertainty in attempting to employ a standard light in these experiments, and the light to work to a thousandth of a degree.

recommended is that from the crater of the positive pole of the It is, perhaps, the greatest advantage of this particular form electric light, or from a petroleum lamp, when the illumination of differential air-thermometer, that this troublesome and un- need not be so intense. The luminosity of the pure spectrum certain correction can be completely eliminated both from the colours may be measured by what the author calls the colour observations and from the calculations by simply duplicating the patch apparatus, which is described in the Phil. Trans., 1886, connecting tubes—that is, by making the thermometric and and in his book on “Colour Measurement and Mixture.” The standard bulbs communicate with similar sets of connecting luminosity of a colour is not the same when viewed from all tubes fixed side by side in such a way that their mean tempera- parts of the eye. The luminosity of any pigment on paper can tures are always equal. Provided ihat the two bulbs contain be found by rotating it with two or three colours, red, emeraldequal masses of air, and that their pressures are adjusted to green, and ultramarine. The colour of a pigment can be reequality, any change in the temperature of the connecting tubes Terred to the spectrum colours by measuring the absorption. will affect both equally, and will not, therefore, alter the read. / The mixture, in varying proportions, of red, green, and violet of ing of the pressure-gauge.? In this way not only is the work of the spectrum, makes white. Any other colour can be matched taking and reducing the observations immensely simplified, but by the mixture of the same three colours. Since three colours the results are also rendered much more accurate.

will make white, and the same three colours will make a match The form of instrument above described is designed for the with an impure colour, every colour in nature can evidently be most accurate work. For rough purposes, and especially for matched by mixing not more than two of these colours with a limited ranges of temperature, for which the auxiliary bulb can certain proportion of white light, and if these colours be red and be dispensed with, much simpler instruments may be constructed green, or green and violet, the colour can be matched by one and compensated on similar principles.

spectrum colour and white light, since there is some intermediate In ordinary work it would be inconvenient to have to keep colour which has the same hue as the mixture of these two the standard bulb always at a constant temperature. The

colours. Hence any colour may be expressed in terms of white necessity for this may, however, be avoided by adjusting the light and one spectrum colour, the latter in wave-lengths and the quantity of sulphuric acid in the pressure gauge so that its ex. former in percentage of luminosity. The lecturer performed pansion compensates for the increase of pressure in the standard experiments in illustration of all the points brought forward. bulb due to rise of temperature of the surrounding air. When

The importance of using some uniform light was insisted upon the instrument is thus compensated, one of the tubes of the throughout. In conclusion the lecturer claims to have demonpressure gauge can be directly graduated in degrees of tempera- strated that the reference of colours to numbers is not only ture. The indications are then as easy to read as those of a possible but easy. mercury thermometer. Such thermometers are very convenient December 3.-Prof. A. Crum Brown, F.R.S., in the chair. for rough work at temperatures beyond the range of mercury The following papers were read :—Phosphorous oxide, Part ii., ' The equations and conditions of compensation are fully given in the

1

* An air-pyrometer and also a long-distance thermometer of this pattern

are made by Mr. J. J. Hicks, of Hatton Garden, E.C.

paper.

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