360 

measurements that I was able to apply, the comet seemed always 
slightly in advance of the position computed by Pechiile. On 
July 17, at 124 15", Dublin mean time, I first found Comet II., 
the cloudy weathe! having rendered a previous search ineffectual. 
This comet was of extreme faintness, and without the sharpest 
attention it might easily pass unnoticed across the field. When 
first observed it was in contact with a small star, not identified, 
from which it gradually detached itself, and its position seemed to 
agree well with Pechiile’s calculation. It was best seen with 56 
and 99, and with the latter, after intent gazing, the momentary 
flickerings of minute points in its misty form could be caught at 
instants of good definition. This so strongly suggested the ap- 
pearance of a nearly resolvable cluster that I was not satisfied | 
with the comet’s identity until I perceived its motion. Previous 
to this observation I had not read the description of the object 
by Herr Tempel, the discoverer, but subsequently I was pleased 
to see his allusion to its appearance as if ‘sprinkled’ with little 
stars towards the middle. If the light of the comet is sufficient, 
T shall not be surprised to hear of its giving indications of acon- 
tinuous spectrum in addition to the usual bright lines.” Mr. 
Charles Hill, of Bristol, also observed Comet II. on July 18, 
and found that it was an exceedingly faint object. It was scarcely 
perceptible in his 8} in. equatorially mounted reflector. 
Venus.—Mr. Henry Ormesher has succeeded in detecting the 
dark markings on several recent occasions. On April 22 they 
were rather pale, but the terminator was clear and well defined. 
On May 10 they were well seen, and appeared to him to be very 
similar to the dusky markings on the surface of Mars. On May 
21 and 29 he also saw the markings. Mr. H. W. Hollis exa- 
mined the planet on July 17, at 6 30", with his 6in. O.G. 
power 159. ‘‘The rounding off of the southern cusp was evi- 
dent at a glance, and the prolongation of the northern one more 
remarkable than I have ever seen it before. A dusky ill-defined 
spot, of uncertain shape, was visible. On the 18th, at 5h 15m, I 
suspected the presence of this spot again somewhat nearer the 
terminator, but of this I cannot speak positively.” Mr. John 
Birmingham, of Tuam, writes: ‘‘I have been carefully obsery- 
ing Venus at every opportunity without detecting any definite 
markings besides the well-known peculiar forms exhibited by the 
cusps, Which appear to me brighter than other parts of the 
planet. 
Saturn.—Mr. H. W. Hollis reports as follows :—‘‘ On July 17, 
at Ioh 20", I inspected Saturn on the meridian, and notwith- 
standing his low altitude, found the shadow of the ball upon the 
the rings clearly visible. I could trace Ball’s division all round 
in moments in fine definition. But what especially interested 
me was that, under a power of 250, the eastern opening between 
the ball and the inner ring was unmistakeably wider than the 
western one. Of this I am certain. The air was too unsteady 
to admit of any operations with the micrometer.” 
Paris 
Academy of Sciences, August 14.—M. Faye in the chair. 
M. Dumoncel sent a note on the Influence of Electrodes in the 
Generation of Electricity. It is well known already by every work- 
ing electrician that a cool surface may be enlarged with advantage 
for a certain distance and surface of zinc.—M. Demosquay sent 
a paper, which showed that many Communist Nationals were 
wounded when intoxicated. The result of it was an immense 
mortalityamongst them, which could not be prevented by the most 
assiduous care. The temperature of the patients was remarkably 
low, which is always indicative of great danger.—M. Arson, 
chief engineer of the Parisian Gas Company, has conducted with 
great care for many years experiments with the view of correcting 
the compass from every variation produced by the iron containel 
in ships. These experiments were worked out in the great La 
Villette gas works, where the company keeps about twenty large 
gas-meters. A commission appointed for the purpose will in 
course of time publish an elaborate report. M. Lependry, en- 
gineer of the canalisation in the same company, has commenced 
to study all accidents analogous to the extraordinary gas- 
lighting by thunderbolts, described in M. W. de Fonvielle’s 
memoir.—M. Resal, an engineer in the mining service, sent 
a note showing that connecting chains as they are used 
by railway carriage constructors are not strong enough.—M. 
Durand Claye, an engineer in the Ponts et Chaussées, sent a 
paper strongly advocating a radical change in the way of dealing 
with the sewage of Paris. ‘The learned engineer shows, by con- 
clusive arguments, that it is absolutely necessary to deal with 
these refuse waters according to the British system, as worked 
for years in Edinburgh, &c., &c. It is not the first time that 
NATURE 

| Aug. 31, 1871 

.| 
learned members of our scientific administration have tried to — 
naturalise that excellent method. But every real progress was” 
stopped by the prevalent system of Imperial red tape and cor-— 
ruption. It is to be hoped that the French Republic will not 
lose time in putting an end to the disgusting waste of manure 
now permitted to poison a noble stream. M. Durand Claye pro- 
posed to irrigate the celebrated Gennevilliers peninsula, whose 
extent is only 5,000 acres.—M. Leverrier read a report on ob- 
servation of the August meteors, of which a summary was pub- 
lished in the Zimes of August 17. 
M. Coggia stating that his bolide was not an imaginary one. 
M. Elie de Beaumont expressed an opinion that possibly that 
extraordinary bolide was not of planetary origin, but merely some 
fire formed in our superior atmosphere, possibly by the agency of 
electricity. M. Henry Sainte-Claire Deville read a memoir 
written by MM. Nagi and Hautefluelle, two teachers in the 
normal school, on a peculiar fact of chemistry relating to a com- 
bination of chlorine of silicium, which appears to be destroyed 
from 700° to 1,000° C., and to be formed again from 1,000° C, 
to 1,500° C.—M. Charles Sainte-Claire Deville read a short 
note on a stroke of lightning which exploded within his meteoro- 
logical observatory, two hours only before an academical sitting 
had taken place. The natural electricity was attracted by a 
leaden tube, in which an isolated metallic wire belonging to the 
telegraphic system of the observatory had been inserted. The 
leaden tube had performed the part of a condenser, and the spark 
was created on the spot of the explosion as the primary wire was 
in connection with the earth. 


BOOKS RECEIVED 
Encuisu.-—Bird Life, Part 1: A. E. Brehon(Van Voorst). 
ForeiGn.—(Through Williams and Norgate).—Geschichte der Glycosurie 
von Hippokrates bis zum amfange des Neunzehnten jahrhunderts : Dr. Max 
Solomon.—Ueber die Helligkeitsverhiiltnisse der Jupiterstrabanten: Dr. R. 
Engelmann.—L’Homme pendant les Ages de la Pierre: M. E. Dupont. 
PAMPHLETS RECEIVED 
EnGutsH.—British Railway Reform: J. H. Watson.—Western Chronicle 
of Science.—Cassell's Book of Birds, Part XXII.—On the Spirit Circle: 
Emina Hardinge.—Transactions of the Boys’ Literary Society, Sidcot School, 
1870-71.—Sidcot School Board Chronicle. 
AMERICAN AND CoLoNnIAL.— What are they doing at Vanar?—Fourth 
Annual Report of the Trustees of the Peabody Museum.—Transactions of 
the Entomological Society of New South Wales, Vol. ii., Part 2. 
ForeiGNn.—Bulletin de la Société de Géographis for May, June, and July, 
1871.—L Institut, No. 1,921.—Allegemeine fiir Deutschland, No. 33.—La 
Tour du Monde, No. 565.—La Révue Scientifique, No. 9.—Rendiconti, 
Vol. iv., No. 15. 


CONTENTS 
PacE 
On THE Various Tints oF Fottacre. By H.C. Sorsy, F.R.S.  . 341 
Human ANATOMY AND PHYSIOLOGY. . . . . ...-+ +» © «© 343 
Our Book“Sueur ei) 6) cee le) foe ToL eat aes On 343 
LETTERS TO THE EDITOR :— 
Thickness of the Earth’s Crust.—Archdeacon J. H. Pratt, F.R.S. 344 
Meteorology in South Australia.—M.M. Finniss . . . . « « 345 
The Solar Aurora Theory.—C. A Younc. .. . os 6 Rp 
Lecture Experiments on Colour.—A. H. ALLEN, F.C.S. . . . . 346 
Mr. Stone and Prof. Newcomb.—R. A. Proctor, F.R.A.S. . . 346 
Saturn’s Rings.—R. A. Proctor, F.R.A.S. oy Bee 
A Rare Phenomenon.—A. Sprunc. «eth te eee + 346 
Tur Aurora. By the Lord Linpsay. (With Diagram) - . 347 
Fruit Crassirication, By Avex. Dickson,M.D. ... .. « 347 
NoTEs. =. . = « Sy Weeks D's ee aie) fe) ley Sie ade 
OssERVATIONS OF LuMINOUS METEORS IN THE YEARS 1870-71 . 


35° 
Tue LATE Rev. W. V. Harcourt’s RESEARCHES ON GLASS. 351 
Tue BritisH AssocIATION.—EDINBURGH MEETING, 1871. 
Sectional Proceedings -mr- ainlcaaati el omnes 5 352-359 
SCIENTIFIC SERIALS || tetas ima mols fo meCune cht UE Tare as 359 
SOCIETIES AND ACADEMIES . . » « « = - « « « « Geo 
Books AND PAMPHLETS RECEIVED...» . « e 5 360 
NOTICE 
We beg leave to state that we decline to return rejected communtica- 
tions, and to this rule we can make no exception. 
j 
He read also a letter from 
