August 12, 1886| 
NATURE 
355 
on Brazilian topaz. The author refers the phenomena to the 
presence of a single electric axis, inclined to each of the three 
principal axes of the crystal. He also points out that the two 
optic axes do not make equal angles with the greatest of the 
three principal axes. —W. Stscheglajeff, on the electro-magnetic 
rotation of the plane of polarisation in chloride of iron. Curves 
given show that in this substance Verdet’s rule that the rotation 
is proportional to the intensity of the field is not observed. H. 
Haga, experimental researches on the convection of heat by the 
electric current. Careful experiments described in this paper 
show that the Thomson effect in mercury is negative.—Fr. 
Stenger, on phenomena of fluorescence. Some doubt having 
been thrown upon the transmutation, by Magdala red and other 
bodies, of red rays into orange or yellow rays, the appearance 
of these higher rays being attributed to stray light, the whole 
matter has been repeated with the utmost precautions. It 
appears to be now established that eosin and fluorescein also 
have this property. All three bodies are exceptions to Stukes’s 
rule that the transmutation in fluorescence is always a degrada- 
tion in the spectrum scale. The author also discusses the matter 
in relation to Lommel’s theory and to the influence of solvents. 
—E. Ketteler, a remarkable limiting case of crystalline re- 
flection, and its investigation by the aid of the perfected total- 
reflectomer of Kohlrausch.—G. Hansemann, on a new method 
of determination of periods of oscillation of bar-magnets. A 
photographic camera and a mirror oscillating in conjunction with 
a seconds pendulum are applied to the ordinary apparatus for 
observing oscillations by reflection.—Werner Siemens, on the 
conservation of energy in the atmosphere of the earth. A dis 
cussion of atmospheric laws and of ws v.va_of the atmospheric 
masses, too involved fora brief abstract.—R. Gerhardt, on the 
tube-flute stop of the organ. An experimental and mathemati- 
cal discussion of the effect of putting a small open tube into the 
closed top of the flute pipe. —W. Alexejew, on solutions. The 
author arrives at the following conclusions: solids dissolve 
better than liquids ; at one given temperature a solid can give 
only one saturated solution, a liquid two; supersaturated solu- 
tions have two temperatures of decomposition, one at which 
decomposition may occur, another at which decomposition must 
occur. A large number of data of observation are plotted in 
curves.—E. Himstedt, reply to the observations of Lord Ray- 
leigh upon my determination of the ohm.—L. Graetz, on the 
dependence of the elasticity of caoutchouc upon temperature, 
and its relation to coefficients of thermal expansion, From his 
observations the author predicts that a twisted rod of caoutchouc, 
when suddenly further twisted, will warm itself.—Fr. Stenger, 
simple demonstration of residual electric charges, by means of 
an exhausted tube used as a Leyden jar.—A. Oberbeck, remarks 
on my work on the resonance of electric oscillations. An ac- 
knowledgment of the priority of Dr. J. Hopkinson. —A. 
Konig, on an observation respecting the empirical basis of our 
perception of space. This basis is the apparent extent of the 
objects in the field of vision as distributed over the retina, and 
their relative apparent displacement when the eye is turned 
about.—Fr. Stenger, correction to the memoir on the properties 
of calc-spar in a homogeneous magnetic field. 
Rivista Scientifico-(ndustriale, June 30.—On some new regis- 
tering thermic instruments, by Prof. Filippo Artimini. A full 
description, with illustrations, is given of the author’s register- 
ing thermo-pyrometer, in which the degrees of temperature are 
accurately recorded by an ingenious application of electricity.— 
Telephoning at great distances, by F. van Rysselberghe. The 
author gives a summary of his recent experiments in the United 
States, showing the possibility of telephoning at any distance 
and establishing a regular international telephonic service be- 
tween all the great cities of the world. The telegraphic wires 
now in use may be utilised for the simultaneous transmission of 
telegraphic and telephonic messages. 
SOCIETIES AND ACADEMIES 
SYDNEY 
Royal Society of New South Wales, June 2.—Chr. 
Rolleston, C.M.G., President, in the chair.—Papers read :—A 
new species of Ardisia from New Guinea, by Baron Ferd. von 
Mueller, K.C.M.G., F.R.S., descriptive of the only specimen 
_as yet found so far north.—A comparison of the dialects of East 
| and West Polynesia, Malay, Malagasy, and Australian, by the 
_ Rey. George Pratt, author of a dictionary of the Samoan lan- 
guage. ‘his was a valuable contribution towards a polyglot of 
the languages of Polynesia, seme of which have already passed 
away, and most of which are changing through the introduction 
of new words and the rapid intermingling of various races. The 
Royal Society of New South Wales was urged to take steps to 
preserve these records and customs not only of Polynesia, but of 
the fast-diminishing tribes of Australia.—The discovery of a 
poison in three species of Daphnandra, a genus of plants of the 
order Monimiacez, by T. L. Bancroft, M.B. (Edin.), F.L.S. 
(Brisbane).—On some new poisonous substances discovered on 
the Johnstone River, North Queensland, also by Dr. Bancroft. 
These papers were descriptive of experiments of the therapeutic 
action on the guinea-pig.—Prof. Liversidge, F.R.S., exhibited 
and described: (1) a meteorite, the third one known to be 
found in New South Wales, composed of iron principally, 
nickel, cobalt, :ulphur, phosphorus, and carbon ; (2) the matrix 
of the rock of the tin deposits of Tasmania, in which the cement- 
ing material is topaz; (3) a collection of New South Wales 
silver ores (38 specimens), collected by Mr. McGarvie Smith ; 
(4) shale from the Hawkesbury sandstone showing worm tracks 
and perforations, the first time noticed in these rocks.—Mr. 
Lawrence Hargrave exhibited a model illustrating the undu- 
latory motion of serpents, based upon the trichoidal plane, a 
continuation of similar studies by him on the motion of fishes 
and the flight of birds. 
Microscopical Section.—The following papers were read 
during the year 1885 :—The Phylloxera vastalrix, by Dr. Morris, 
illustrated with specimens of the diseased vine from the neigh- 
bourhood of Sydney ; and by the same author, Notes on mount- 
ing diatoms in highly refractive media.—Specimens of A. pellucida 
were exhibited mounted in piperine, picric acid, chlorides of tin, 
and thallium, and sulphur in combination with disulphide of 
arsenic. These slides were exhaustively tested against the 
American methods, viz. Dr. Chase’s metallic silver and realgar, 
also Prof. Smith’s (Geneva, N.Y.) specimen slide. - The micro- 
scopes and accessories were of the latest make, and the objectives 
used were homogeneous immersions by Tolles, 1/10, 1/25 ; 
Spencer, 1/12; Powell, 1/12, 1/20. The slides of Dr. Morris’s 
sulphur and arsenic combination gave the best results. In addi- 
tion to the above-mentioned objectives the following choice 
glasses were acquired by members of the section during the 
year :—Powell’s, 1/6; Hom N.A., 175; Green (late Tolles), 
1/2” 30°; Bausch and Lomb’s, 1/16 immersion ; Wales, 1/12 
immersion, 170°. A valuable Ross Zentmeyer binocular stand 
with apparatus was presented by H. G. Wright, M.R.C.S.E., 
whilst immersion and high-angled condensers were purchased. 
Amongst the numerous slides exhibited were some of new mosses 
found in the neighbourhood of Sydney by Mr. Whitelegge, and 
a bacillus found by Dr. Morris in the ulcerated intestine of a 
foal, the cause evidently of a widely spread epidemic prevalent 
throughout the colony amongst young foals only. 
Paris 
Academy of Sciences, August 2.—M. Jurien de la 
Graviere, President, in the chair.—On the relations of geodesy 
to geology, by M. H. Faye. In this second communication it 
is shown that the harmony of the two sciences results in the 
remarkable law determining the constancy of the mathematical 
figure of the globe throughout the whole series of geological 
evolutions, a law which sooner or later will enable us to form a 
clear idea regarding the thickness of the present crust of the 
earth. At the same time the problem cannot be completely 
solved by the resources of geometry alone, and recourse must 
be had to the other sciences bearing on the subject.—On the 
displacement of ammonia by other bases, and on its quantitative 
analysis in the soil, by MM. Berthelot and André. From their 
further researches the authors conclude that magnesia cannot be 
safely employed for the quantitative analysis of ammonia in the 
analysis of the earths and other organic products containing in- 
soluble double ammoniacal salts. Certain derivatives from the 
aldehydes are in the same position, as are also probably the 
ammoniacal salts formed by the humic and allied acids. —On the 
quantitative analysis ofammonia (continued), by M. Th. Schlcesing. 
Having previously shown (July 26) that by distillation on magnesia 
all the ammonia may be extracted from the solution of its hydro- 
chlorate, or from that of the ammoniaco-magnesian phosphate, 
the author completes his demonstration by causing the magnesia 
to act on the double ammoniacal salts, and especially on the 
chlorides containing magnesium and zinc.—Observations on the 
oldest sedimentary groups in the north-west of France (con- 
tinued), by M. Hebert. A careful study of the whole regior. 
