22 
nation is made of the characteristic modifications experienced by 
iron at a temperature of about 700° through the extremely rapid 
absorption of heat in a comparatively slight interval of tempera- 
tures. —Conditions under which is realised the maximum of useful 
work in an electric distribution, by M. Vaschy.—Note on atmo- 
spheric refraction, by MM. J. Chappuis and Ch. Riviere. This 
phenomenon is here studied by a method based on the em- 
ployment of Jamin’s interferential refractometer.—New facts 
bearing on the phenomenon of the apparent oscillation of the 
stars, by M. Aug. Charpentier. Several observations are made, 
tending to show that the phenomenon is of a purely subjective 
character, due especially to the unequal fatigue of the muscles 
of the eye, or rather to their innervation.—On the presence of 
a new element in samarskite, by Mr. W. Crookes. The already 
described abnormal orange band A = 609 = 572693 which the 
author supposed due to a mixture of the two earths yttrium and 
samarium, he now finds cannot be due to either of these, the 
only probable alternative being that it belongs to some new 
element. Until it can be separated from the asssociated sub- 
stances and its chief properties determined, he proposes to name 
it Sa, the initial letter S indicating its samarskite origin.—On 
the dissociation of the hydrates of the sulphate of copper, by 
M. H. Lesecceur.—Action of the acids and bases on emetic 
solutions, by M. Guntz.—Action of water and of ammonia on 
the chloride of methylene, by M. G. André.—Some new pro- 
perties of cyanated camphor, by M, Alb. Haller.—A contribu- 
tion to the study of the alkaloids, by M. Géchsner de Coninck. 
The author applies the method of MM. Hoogewerf and Van 
Dorp to the treatment of some iodides of pyridic ammonium— 
isomethylate of pyridine, C;H;N,CHgI, and_iodethylate of 
pyridine, C;H,N,C,H,I.—On the normal dinitriles 
CN—(CH,),—CN, 
by M. L. Henry.—Chemical researches on the products of the 
eruption of Mount Etna during the months of May and June 
1886, by M. L. Ricciardi. The sands collected at Cibali were 
of a blackish colour, consisting mostly of amorphous detritus 
mixed with crystalline fragments of labradorite, olivine, and 
_ pyroxene readily affected by the magnet. The ashes ejected on 
May 28-29 present similar characteristics with a larger quantity 
of salts soluble in water.—Volumetric analysis of the sulphur in 
the sulphides decomposable by hydrochloric or sulphuric acid, 
by M. Fr. Weil. —Researches on the growth of beetroot, by M. 
Aimé Girard. This paper deals especially with the stalk, which 
during growth consists of a tissue, in the elementary organs of 
which water and sugar, forming a constant quantity, are mutually 
replaced according to the circumstances.—Kesearches on the 
structure of the scorpion’s brain, by M. G. Saint-Remy.—On 
the structure of the germ vesicle in S%phonostoma diplochatos, 
Otto, by M. Et. Jourdan.—On the post-embryonic evolution of 
the vitelline sac in birds, by MM. Charbonnel: Salle and Phisalix. 
—On the vascular system of Spatangus purpurens, by M. H. 
Prouho.—On the glands of insects: a pretended ‘‘new type of 
elastic tissue,” by M. J. Gazagnaire. The paper deals espe- 
cially with the unicellular glands first described by Meckel in 
1846, and afterwards studied by Stein, Sirodot, Leydig, and 
others. To these are referable M. H. Viallanes’ pretended 
‘elastic cellules.’—On some histological peculiarities of the 
digestive tube in the simple Ascidians, and especially the 
Cynthie, by M. L. Roule.—On the geological constitution of 
the Pyrenees: the Triassic system, by M. E. Jacquot. The 
author's investigations lead to the conclusion that along the 
French slope, from the banks of the Nive to the Teck valley, 
the Triassic formation presents a uniform composition, recalling 
that of the ranges in Franche-Comté, Provence, and Lorraine. 
BERLIN 
Physical Society, May 21.—Dr. Kénig spoke on the 
modern attempts towards laying down an _unexceptionable 
basis of mechanics. Among the axioms of mechanics the law of 
inertia set up by Newton was the most important, but neither the 
conceptions of time, which lay at the basis of the idea of uniformity, 
nor the conception of the straight line, were precisely definable 
without further assumptions. A whole series of attempts had 
been made to fix these fundamental conceptions, attempts which 
the speaker briefly sketched. He came to the conclusion that 
as standard of time not the movement of translation, which could 
never be absolutely measured, but the movement of rotation 
must be recognised. The movement of rotation was perceptible 
NATURE 
[xudy 1, 1886 
in itself, namely, through the oblateness of the rotating ball. 
With regard to the straight line, that is with regard to our co- 
ordinate system in space, the speaker accepted the ideas set 
forth last year by Herr Lange of Leipzig, who started with a 
notion developed by Prof. James Thomson of Glasgow. Dr. 
Konig gave a graphic representation of the idea which had been 
only mathematically developed and established. According to 
this representation it was possible, when three points de- 
scribed in a particular space any paths whatsoever, to follow with 
a co-ordinate system these movements in such a manner that all 
three points moved rectilinearly. Experience taught that when 
three points described straight lines to such a co-ordinate system, 
each fourth, fifth, and so on, did it as well. Thus in the move- 
ments of rotation, and in the mobile co-ordinate system, unexcep- 
tionable bases of mechanics might be found whereupon to raise 
asuperstructure, just as mathematics was built up on its axioms, 
BOOKS AND PAMPHLETS RECEIVED 
“Official Guide to the Museums of Economic Botany, Kew,” No. 1, 
‘*Dicotyledons and Gymnosperms,” 2nd edition(Eyre and Spottiswoode).— 
“Quarterly Journal of Microscopical Science,’* June (Churchill),—“ Chad- 
lenger Reports,” vol. xiv. ‘‘Zoology.”"—‘‘ Hygiene of the Vocal Organs,” 
by Dr. M. Mackenzie (Macmillan).—‘‘ Disorders of Digestion ; their Conse- 
quences and Treatment,” by Dr. T. L. Brunton (Macmillan).—‘‘ Photo- 
Micrography,”’ by I. J. Jennings (Piper and Carter).—‘‘ Birds on the British 
List,” by Rev. G. Smart (R. H. Porter).—‘' Proceedings of the Linnean 
Society of New South Wales,” vol. x. part 4 (Cunninghame, Sydney) — 
© Proceedings of the Physical Society of Moscow,” tome viii. No. 2.— 
““Bourne’s Handy Assurance Directory, 1886” (Bourne, Liverpool) — 
“Jouraal of Anatomy and Physiology,” July (Williams and Norgate).— 
“General Index to the Year-Book of Pharmacy for the Years 1864 to 
1885” (Churchill).—‘‘ The Great and Growing Question of Vaccination” (E. 
W. Allen).—‘‘Studies from the Biological Laboratory, Johns Hopkins 
University,” vol. iii. No. 7. 
CONTENTS PAGE 
Kepler’s Correspondence with Herwart von Hohen- 
burg. By Miss A. M.(Clerke. = . <=: . =) @ sso 
Upland and Meadow. ........--5.-. 190 
Letters to the Editor :— 
On Refractometers.—Dr. J. H. Gladstone, F.R.S. 192 
Luminous Boreal Clouds.—D. J. Rowan. . ... 192 
Ampére’s Rule.—W. L. ; L. Cumming ; George 
M. Minchin: “((Z/dustrated) . 3s.) ~ 2 8 
An Earthquake Inyention.—Prof. John Milne 193 
Professor Newcomb’s Determination of the Velocity 
of Light.—Miss A. M. Clerke . .....--. 193 
Solar Halo and Sun Pillar seen on June 5, 1886,— 
FA; Bellamys (iustrated))~ 2) = el Oe 
The Enemies of the Frogy.—H. Ling Roth .... 104 
Chronology of Elasticians.—Prof. Karl Pearson . 194 
Solar Meteorology Stor eea be ey cio fot eh onl ele 
Seismology in Japan. By Prof. J. A. Ewing . . 195 
Recent Advances in Sanitary Science ...... 196 
Sale of the Jardine Ornithological Collection ... 199 
Notes: 9.2 SC at eine is fe fe ied deve) ce" moll loyure ti e'ate! fefoMto MMe MmmERC LES 
Our Astronomical Column :— 
Black Transit of Jupiter’s Fourth Satellite... .. 202 
Gomets Brooks I. and TIT; . . 3... 3 j= 6 202 
Nova. Orionis: 4 c:) s1 eo ce. cele. is, schol Mle. te) (sale ECS 
TO Sagittee | mp se 2 oie 
Astronomical Phenomena for the Week 1886 
NtiN 77 Clan een ORG TOREONONOEONONONONOIG GOO) 25. 
National Smoke Abatement Institution. By E. 
White Wallis ca gee ets aaky uey fe ee. acetone 
The Wings of Birds. By Prof. W. H. Flower, 
FOR So 2 POA cb ef SR eee Se ee 
The Sun and Stars, VII. By J. Norman Lockyer, 
FUR ISo (Zidstrated)\ Pe) eee ae eae ee 206 
Scientific ‘Serials\..«. sc, ces) ys os oun 
Societiessand: Academies). ys @/= (0 ie) eee 
Books ani Pamphlets Received .......+. 
a ee he ee 
