202 
NATURE 
[Fuly 7, 1870 
“« May it please your Royal Highness. —On behalf of the Meteo- 
rological Society, and as Government Observer, I have the honour 
to thank your Royal Highness for having been graciously pleased 
to lay the Foundation Stone of the Mauritius New Observatory. 
‘*T am sure I only give expression to the feelings with which 
the Society is animated, when I say that it will ever retain a 
most grateful sense of the generous sympathy and consideration 
which have induced your Royal Highness to come here, to-day, 
at personal inconvenience, to perform the interesting and impor- 
tant ceremony which the Society has had the extreme gratitica- 
tion to witness. 
“If anything could enhance the pleasure which the Society 
now feels, it is the presence, on this auspicious occasion, of his 
Excellency, Sir Henry Barkly, who, during a long and an arduous 
administration, has not ceased to take a warm interest in the 
Society’s objects, and to whom will be mainly due the merit of 
establishing in this distant Colony an Observatory which, I hope, 
will be second to none of the same nature in other portions 
of Her Majesty’s dominions. 
“Engaged for the most part in agricultural and commercial pur- 
suits, but yet dependent for the necessaries of life on importations 
from other countries, and surrounded by a tempestuous ocean, 
the people of Mauritius, deeply interested in the progress of 
meteorological science, and many of them actively occupied in 
promoting it, will, I have no doubt, long preserve a fond recol- 
lection of the part which your Royal Highness has been kind 
enough to take in this day’s proceedings. 
‘*But the labours to be carried on here will be not merely of local 
utility. I trust they will also contribute to the advancement of 
meteorology and of terrestrial magnetism generally, as well as 
of certain branches of physical astronomy. In this respect their 
chief practical aim will be to render service to the noble profes- 
sion of which your Royal Highness is so. distinguished a 
member ; and next to the pleasure of contemplating the works of 
the great Author of Nature, I know no stronger incentive to 
perseverance than the circumstance that the building about to be 
raised on this solitary spot, in the heart of the Indian Ocean, for 
the special object of conducting researches calculated to be of use 
to the maritime nations of the world, will in all future time be 
associated with the cherished name of England’s sailor Prince.” 
His Excellency the Governor briefly addressed the audience. 
His Excellency said that he had always, as Mr. Meldrum re- 
marked, taken much interest in the Society, and had done all in 
his power to promote its objects. It gave him great pleasure that 
the foundation stone of a new observatory had been laid before his 
departure from the colony. The ceremony could not have been 
more appropriately or more gracefully performed than by his 
Royal Highness, who was not only the second son of Her Majesty 
the Queen, but also a distinguished naval officer. His Excel- 
lency concluded amid general applause, by heartily wishing every 
possible success to what he would propose to call the Royal Alfred 
Observatory. Thus terminated these interesting proceedings. 
SCIENTIFIC SERIALS 
Sournal of the Chemical Society, June, 1870.—Messrs. T. Bolas 
and C, E. Groves give a description of the mode of preparation 
and the properties of tetrabromide of carbon, the discovery of 
which they had announced in the preceding number of the 
Journal. Bisulphide of carbon was digested with an excess of 
bromine in the presence of terbromide of antimony or of bro- 
mide of iodine in a sealed tube of 150° for 48 hours, The 
bromide can also be obtained from bromopicrin and bromoform 
by treatment with the same reagents. Tetrabromide of carbon 
crystallises in white lustrous plates, fusible at 91°, nearly in- 
soluble in water, soluble in alcohol, ether, benzol, and bisulphide 
of carbon, decomposed by aqueous solutions of potassa and soda 
at 150°. With care it may be sublimed without decomposition. 
By reduction by nascent hydrogen it produces bromoform and 
dibromide of methylene. The authors intend to study the action 
of argentic oxalate, cyanide, &c., on this interesting compound. 
Prof. A. H. Church continues his researches on new and rare 
Cornish minerals, giving the analysis of restormelite, which 
appears to be kaolinite Al, O, 2SiO,, 2Aq, in which some of the 
hydrogen is replaced by potassium and sodium and a portion of 
the aluminium by iron. The specific gravity is 2°58, and the 
hardness about 2. Chalcophillite contains 8 CuO, Al, Og, 
As, O;, 24 or 25 Aq., it loses 13°79 per cent. of water 77 vacuo, 
corresponding to 11 H,O; the specific gravity is 2°44. This 
number also contains the commencement of a very long and 
elaborate paper on the combinations of carbonic anhydride 
with ammonia and water, by Dr. E. Divers. The author gives 
a history of the different compounds which he has examined, 
and describes no less than nine processes for the preparation of 
normal ammonium carbonate CO, (O H,).(NH.),. Its properties 
and reactions are also fully given. In the second section, only 
a portion of which appears in this number, the preparations and 
propertics of the half acid ammonium carbonate are detailed. 
THE Revue des Cours Scientifigues for June 18, is almost 
entirely occupied with a translation of Prof. Huxley’s address 
before the Geological Society on the course of palzeontology during 
the last eight years. M. Bernard also proceeds with his course of 
lectures on suffocation by the fumes of charcoal, which is again con- 
tinued in the following number, where we find also a paper read 
before the Congress of German Naturalists and Physicians at 
Innsbriick by Prof. Kékulé, on chemical work, and a review by 
Prof. Duclaux, of Pasteur’s Researches on the Silkworm 
Disease. In the number for July 2, is a very important article 
by Prof. Agassiz on the Gulf Stream, being a report of the 
dredgings from the bottom of the Gulf Stream, made during the 
third expedition of the U.S. steamer 44d. Prof. Agassiz believes 
that in the cretaceous period a current set in in the Atlantic from 
the north-east to the south-west, North and South America being 
then distinct continents, and that it was only at a subsequent 
period that communication between the Atlantic and Pacific 
became interrupted, and that the Gulf Stream set in in the op- 
posite direction. In the same number is a continuation of M, 
Berthelot’s paper on isomeric states of simple substances, treating 
especially of sulphur. 
SOCIETIES AND ACADEMIES 
LonDON 
London Mathematical Society, June 9.—Prof. Cayley 
President, in the chair. The Hon. Sir James Cockle was 
elected a member. Mr. Spottiswoode, V.P., having taken the 
chair, the president communicated the following “Note on 
the Cartesian, with two imaginary axial foci.” Let A, A’, B, BY 
bea pair of points and antipoints ; viz., A, A’, the two imaginary 
points, co-ords (+ B/, 0); B, B’, the two real points, co-ords 
(0, + B), and write p, p’, a, o’, the distances of a point (x, 4) 
from the four points respectively, say 
p=/(x + Bi)? +7 
a =/ x? + (vy + BP 
we have 
p? + p= 2 (x* + 9°) - 28° 
= +4+o0%-482 
pf m= NI Cee BEY 98) (e+ BE — yi) (> BE ee) 
=o 
p=a/ (x - Bi)? + # 
of =/ a + (y- BP 
and thence 
(p + p')? = (a x 0’)? — 4 B? 
(p= 9p)? = "(0 =i) 2 eae 
or say 
pte =/(o + 0)? 4B 
i(p - P') = 4B = (6 - 0)? 
The equation of a Cartesian having the two imaginary axial 
foci, A, A’, is 
(P+ gi) pt (A6- gp +2h=0 
viz., this is, 
Pip +e’) +gilp—p') + 2k* =0 
or what is the same thing, it is 
PV (o +0)? -48 +948" - (7-0)? +22 =0 
which is the equation expressed in terms of the distances o, o’, 
from the non-axial real foci, B, B’. The radicals are to be 
taken with the signs +. This equation gives, however, the 
Cartesian in combination with an equal curve situate symmetri- 
cally therewith in regard to the axis of y. 
The distance o, o’ may conveniently be expressed in terms of 
a single variable parameter @; in fact, we may write 
&pr/(o +c)? - 4h = - 22 — 20 
+g /4R=(¢—o)? = =~ hk? + kd 
