: April 20, 1871 | 

THE Royal Commission fon Scientific Instruction and the 
Advancement of Science will resume its sittings on the 25th 
instant. 
THE Marine Aquarium at the Crystal Palace is beginning to 
take form, thanks to the energy of Mr. Lloyd. About one-third of 
the 700 tons ( = 150,000 gallons) of the sea water required is 
already in the tanks, but the steam engines and pumps are not 
yet regularly at work. When they are, and some of the marine 
animals of which at present the aquarium is quite destitute shall 
have been received, we hope to give a description of an enter- 
prise of which great scientific use can certainly be made. 
WE learn from the Chemical News that the Council of the 
Federal Swiss Polytechnic School at Ziirich has appointed Dr. 
Emile Kopp as Professor of Technology in the room of the late 
lamented Dr. Bolley. Professor Kopp’s merits, during the time 
he has held the Professorship at the Institute Superiore, at 
Turin, have been gracefully acknowledged by the Italian Govern- 
ment, it having pleased H.M. King Victor Emmanuel to grant 
to Dr. Kopp the dignity of Commandeur de l’Ordre Equestre de 
l2 Couronne d’Italie. We sincerely congratulate Dr. Kopp, and 
no less so the Government of the Helvetian Republic, on having 
secured the services of a man so eminently well suited as Dr. 
Kopp to the important Professorship vacant by the demise of 
Dr. Bolley. 
THE French Academy of Sciences held a short sitting on April 
3, M. Faye, who usually occupies the chair, being, however, 
absent, The principal subject of interest was a sharp passage 
of arms between M. Delaunay and M. St. Claire Deville re- 
specting the Montsouris Observatory. The Commune having 
ordered the arrest of M. Henri St. Claire Deville, the Professor 
of Chemistry in the University, as a hostage, he has been com- 
pelled to make his escape to Versailles, together with his brother, 
the meteorologist. M. Leverrier is also now at Versailles. Dr. 
Bersigny, who conducted the observations during the Prussian 
occupation, will be the director of the meteorological observations 
conducted by the Government. 
THE second soirée of the Royal Society takes place on Saturday 
evening next, and that of the Linnean Society on Wednesday 
the 26th inst. 
WE understand that there is likely to be a contest for the seat 
in the Senate of the University of London, vacant by the death 
of Prof. Miller. The nomination would, in accordance with 
previous practice, be left this time to the Faculties of Science and 
Medicine, and their representative is Dr, Parkes, F.R.S., of Netley, 
who is also supported by many graduates in Arts. 
THE course of lectures during the Easter term at the Gresham 
College, by Dr. E. Symes Thompson, Gresham Professor of 
Medicine, will be on April 21, 22, and 24, the subjects being, 
“©On the Small-pox Epidemic,” “On the Organs of Respira- 
tion,” and “ On the Organs of Circulation.” These will be fol- 
lowed by two lectures on May 24 and 25, ‘‘ On the Water-supply 
of London,” and “On the Heart and Lungs in Health and 
Disease. As usual the lectures are free to the public. 
Tt is rumoured that a College for Women is to be established 
at Cambridge, in order to give the students the advantage of 
attending the lectures, &c., of the University Professors, 
Tue following are places of Comet I., 1871, discovered 
by Dr. Winnecke, for the dates named :—1871, April 7, 
o8 so™ 315, M. T. Karlsruhe; AR app. O = 2h 27" 14°°59 
Decl. app. &% = + 53° 53’ 8"1. April 8, 9 39" 435, M. T. 
Altona; AR app. = 2h 32™ 8°21 ; Decl. app. = +53° Ba AN"Ks 
April 9, gt 56™ 253, M. T. Altona; AR app. = 2" 37" 2°50 
Decl. app. = +52°, 55’ 31''0. 
NATURE 
493 

IN a recent number of Poggendorft’s Annalen, Dr. Weinhold 
states that the black absorption line of sodium can be easily ob- 
tained by a simple process. The usual method has been to in- 
terpose a flame, coloured with chloride of sodium, between a 
strong light, such as the electric light, and the slit of a spectro- 
scope. The source of light now proposed by M. Weinhold is 
an ordinary petroleum lamp ; the light is allowed to pass through 
a slit directly on to a prism, and a spirit lamp flame, intensely 
coloured with chloride of sodium, interposed between the prism and 
the eye, so as to cover the entire spectrum ;—the black absorption 
line will then be seen distinctly. If the flame coloured with sodium 
is placed in front of the slit, the bright yellow line will be seen 
as usual, M. Weinhold has not been successful in using this 
method with an ordinary spectroscope fitted with telescopes, on 
account of various practical difficulties, 
M. GABRIEL MoRTELLET, the sub-conservator of the St. 
Germain Museum, wishes us to correct a statement which seemed 
to imply that it was open during the Prussian siege. This was 
not the case, elthough the works were not interrupted. 
THE temperature of February and March shows a remarkable 
contrast to that of the two preceding months. Mr. Glaisher’s 
tables, published in the Gardener's Chronicle, show that at 
Blackheath on forty-seven days during these two months the 
temperature was above the average, while it was below the 
average on only twelve days, the mean being 3°°55 above that of 
the same period during the last fifty years. The disturbance of 
equilibrium caused by the low temperature of December and 
January has thus almost been restored. During Feburary the 
thermometer only fell to the freezing-point on five nights, and 
during March east winds prevailed to only a very moderate ex- 
tent, showing a very marked contrast to the same month last 
year. The depression of temperature which commenced on 
March 28 continued to April 11, when there was a sudden 
rise from 4°"r below the average to 11°°4 above the mean on 
April 12. 
THE publication is announced of a new series of the ‘‘ Mes- 
senger of Mathematics.” It will be edited by Messrs. W. Allen 
Whitworth, C. Taylor, W. J. Lewis, R. Pendlebury, and J. W. 
L. Glaisher, and the first number will be published by Messrs. 
Macmillan on May Ist. The editors consider that the ‘‘ Messen- 
ger” has, during the five years it has already existed, amply 
fulfilled its object of encouraging original research in the three 
Universities among junior graduates and others, although no 
inconsiderable portion of its contents has been supplied by 
writers of established reputation, who rank amongst the foremost 
mathematicians of the age ; and it is this fact in particular which 
now induces them to appeal directly to the mathematical world 
at large, and to remove from their title-page any words which 
might be supposed to limit the sphere of usefulness of the 
‘*Messenger.” They are therefore prepared to receive com- 
munications from every available source, and have already to 
announce papers, forwarded or promised, by Prof. Cayley, Chief 
Justice Cockle, Mr. Routh, Mr. Esson, and others. Besides 
original papers, it is intended to insert brief notices of select 
articles or treatises on mathematical subjects, as well as short 
accounts of the proceedings of societies at home or abroad. 
THE second series of ‘* Science Lectures for the People,” de- 
livered in the Hulme Town Hall, the first of which we have 
already had occasion to notice in terms of commendation, con- 
tains reports of lectures by Professor W. C. Williamson on 
“‘The Natural History of Paving-Stones,” Dr. W. B. Carpenter 
on ‘The Temperature and Animal Life of the Deep Sea,’ Mr. 
A. H. Green ‘‘More about Coal,” and Mr. Norman Lockyer 
‘On the Sun.” It is published by Mr. John Heywood, Deans- 
gate, Manchester, and Messrs. Simpkin, Marshall and Co., 
London. 
