26o 



NATURE 



\7tuy 15, 1880 



shore, are found in the boulder-clay of the northwest of the 

 island. Again, on the mainland, blocks of the coarse siliceous 

 sandstones which cross the island from Inganess to Orplin are 

 met with in the boulder-clay between Ilonton Head and tlie 

 Loch of Slennis. Moreover, they discovered in the boulder- 

 clay the following rocks, which are foreign to the island : chalk, 

 chalk-flints, oolitic limestone, oolitic breccia, dark limestone of 

 Calciferous-sandstone age, quarlzites, gneiss, &c., some of w hicli 

 closely resemble the representatives of these formations on the 

 east of Scotland, and have doubtless been derived from thence. 

 From this they infer that, while Shetland was glaciated by the 

 Scandinavian mer de glace, Orkney was glaciated by the Scotch 

 ice-sheet, the respective ice sheets having coalesced on the floor 

 of the North Sea .and moved in a north-westerly direction 

 tow-ards the Atlantic. They also found abundant fragments of 

 marine shells in most of the boulder-clay sections, which are 

 smoothed and striated precisely like the stones in that deposit. 

 They conclude that these organisms lived in the North Sea prior 

 to the great extension of the ice, and that their remains were 

 commingled with the fnoraine frofondc as the ice-sheet crept 

 over the ocean-bed. From the marked absence of shell-frag- 

 ments in the Shetland boulder-clay they are inclined to believe 

 that much of the present sea-floor round that group of islands 

 formed dry land during the climax of glacial cold. 



Paris 

 Academy of Sciences, July 5.— M. Edra. Eecquerel in the 

 chair. — The death of M. Eorchardt (correspondent in Geometry) 

 was announced. — The following papers were read : — Study of 

 the variation of the line of sight, on the great meridian circle of 

 Paris Observatory (constructed by M. Eichens), by means of 5 

 new apparatus, by M. Loewy. The essential part is a small 

 glass disk giving simultaneously three images in the eye-piece : 

 (i) that of the cross wires, (2) that of a division drawn on the 

 objective, and (3) that of one of the divisions of a plate inserted 

 in the axis. — On the photography of the chromosphere, by M. 

 Janssen. The exposure is continued till the solar image is 

 positive to the border ; the chromosphere then appears as a dark 

 circle 8" or 10" in width. — On the integration of linear equations 

 by means of the sines of superior orders, by M. Villarceau. — On the 

 consequences of the experiment of MM. Lonlin and de Fonvielle, 

 by M. Jamin. He indicates experiments which should test his 

 explanation. — On the vision of colom-s, by M. Chevreul. — On 

 some general relations between the chemical mass of elements 

 and the heat of formation of their combinations (continued), by 

 M. Berthelot. The influence of mass of the elements in diminishing 

 the stability, and therefore the heat liberated, may be conceived 

 simply by supposing that the system formed by two molecules 

 will be more exposed to destruction by movements of the whole 

 system (rotations, vibrations, &c.,) the heavier the molecules. 

 On the other hand, the reserve of energy (which is gradually 

 expended in combination), should, "ceteris paribus, be greater in 

 light elements than in heavy ones. — Epochs of vegetation for tlie 

 same tree in 1S79 and in 1880, by M. Duchartre. Though the 

 temperature was much m»re severe in December and January 

 last than the previous year, the renewal of vegetation in six 

 chestnuts was earlier. The mild time between the cold 

 of December, 1S79, and January, iSSo, does not account 

 for this, for a longer and milder time inten-ened in 1S78- 

 79. Nor does the method of sums of heat explain it. But 

 the trees received more heat this year from the beginning of 

 vegetation to complete expansion of their leaves. — On a meteorite 

 which fell on November 16, 1874 at Kerilis (Cotes du Nord), by 

 M. Daubree. This belonged to the sub-group Oligosideres in 

 the Sporadosideres. — On a meteorite which fell on September 

 6, 1841, in the vineyards of Saint Cliristophe-la-Chartreuse 

 (Vendee), by JI. Daubree. — Inquiry into the situation of agri- 

 culture in France in 1879, by M. Chevreul.— On the utility of 

 ciuarantines, by M. de Lesseps. He gives examples of their 

 inadequacy. — Nature of the immunity of Algerian sheep against 

 spleen-disease ; is it an ajjtitude of race ? by M. Chauveau. The 

 property is congenital and natural. It may be communicated by 

 crossing to European sheep. French sheep bred in Algeria do 

 not acquire it, and it is not proved that Algerian sheep bred in 

 France may not lose it.— Determination of the difference of 

 longitude between Paris and Bonn, by MM. Le Clerc and De 

 Bernardieres. The figures obtained are 19m. 2'269s., probable 

 error -j- 0-009;. German astronomers found for the same arc, 

 19m. 2-23is.—Some remarks on the equation of Lame, by M. 

 Escary.— Integration of any number of simultaneous e;:iuations 



between a given number ot functions of two independent variables 

 and their partial derivatives of the first order, by M. Turquan. — 

 On the bright spectral lines of scandium, by M. Thalen.- Im- 

 provements in Siemens' bobbins, by M. Trouve. He suppresses 

 the two periods of indifference, making the polar faces of snail 

 form, so that thesurfacesapproach those of the magnet gradually, 

 till the moment that the posterior edge escapes from the pole, 

 when repulsion commences. The work is; tlius economised. 

 — On the sensibility of the eye to differences of light, by 

 M. Charpentier. A given light, strong or weak, must (in his 

 case) be increased or diminished about eight hundredths to give 

 a distinct new sensation ; and it seems to be the same in indirect 

 vision 'as .in .direct, and with coloured as with white light. — 

 Thermic study of polysulphides of ammonium and persulphide 

 of hydrogen, by RI. Sabatier. — On the density of iodine vapour, 

 by M. Troost. He finds it to diminish both at a low and at a 

 high temperature, so that dissociation or isomeric change seems 

 hardly admissible. — On the atomic weight and on some charac- 

 teristic salts of ytterbium, by M. Nilson. — On the dissolution of 

 platinum in sulphuric acid, by M. Scheurer-Kestner. The attack 

 of platinum is always due to presence of nitrogenised compounds 

 in the sulphuric acid. — Remarks on etherification of hydracids, 

 by M. Villiers. — Atmospheric bacteria, by M. Miquel. The 

 number, very small in winter, increases in spring, and is high in 

 summer and autumn ; but while spores of mould are abundant 

 in w et, and rare in dry, periods, it is the opposite with aerial 

 bacteria. At Montsouris, in summer and autumn, 1,000 germs 

 of bacteria are sometimes found in I cubic metre ; in winter the 

 number may go down to 4 or 5, and on some days 200 litres of 

 air are insufficient to infect the most alterable liquors. In ordi- 

 nary houses air proves fertilising (to neutral bouillon) in a volume 

 of 30 to 50 litres. M. Miquel notes an increase of deaths from 

 contagious and epidemic diseases in Paris, about eight days after a 

 recrudescence of aerial bacteria. Water vapour from the ground, 

 rivers, or putrefying masses is always micrographically pure. — 

 On a digestive ferment contained in the sap of the fig, by M. 

 Bouchut. — A work by M, de Koninck, on the fauna of the 

 carboniferous formation of Belgium, was presented. 



VlE.XNA 



Imperial Academy of Sciences, May 7. — B. Bolzano's 

 significance in the histoid of infinitesimal calculation, by Prof. 

 Stolz. — Inve3tig.ation of the roast products of coffee, by Herr 

 Bernheimer. — On direct introduction of carbonyl groups into 

 phenols and aromatic acids (third part) ; behaviour of pyrogallic 

 and gallic acids with carbonate of ammonia, by Prof. Senhofer 

 and Dr. Rrunner. — On Guthrie's cryohydrates, by Herr Offen. — 

 On the relation of the coefficients of diffusion of gases to the 

 temperature, by Herr von Obermayer. — On the coincidence of 

 disorders of the skin and of the grey axis of the spinal cord, by 

 Dr. Jarisch. 



CONTENTS Page 



The New Museum of Natural History 237 



Elementary Education 237 



Argentine Entomology. By W. L. Distant 238 



The Human Voice 239 



Our Book Shelf : — 



Lees' "Keith Johnston's Illustrations of Electricity and Mag- 

 netism" ... 240 



Letters to the Editor: — 



A Fourth State of Matter. — Geo. E. Nswton 240 



Permanent Record of Foucault's Pendulum ^E.\penment. — Chas. 



R. Cross ^ • • ^■♦^ 



The Freshwater Medusa. — Prof. E. Ray Lankester, F.R.S. . . 241 



Artificial Diamonds. — J. B. Hannay 241 



Temperature of the Breath.— Dr. R, E, Dudgeon 241 



Reversals by Memory. — Rev. George Henslow 241 



Toughened Glass. — Noble Taylor 241 



Gre.-it Meteor.— Major G. L. Tupman . - 242 



Iron and Hydrogen. — Walter R. Browne 242 



The Stone in the Nest of the Sw.allow.— William E. A. Axon . 342 



The Caribbean Sea 242 



Albania and the Albanians. By .4. H. Keane 243 



Report OF THE British MusHU.M _. 246 



Marcel Deprez's Galvano-meter for Strong Currknts (/K/M 



Illustration) 246 



Prof. W. H. Miller. By N. Storey Maskelyne, M.P., F.R.S. . 247 



Paul Broca ' . • . : . 249 



The United States Weather Maps, September, 187S 249 



Notes 250 



Meteorological Notes 253 



GEOGRArHiCAL Notes "'• 254 



Artificial Diamonds. By J. B. Hannay. F.R.S.E 255 



University and Educational Intelligence 257 



Scientific Serials 257 



Societies AND .\cadsmies 25S 



