March 3, 1870| 
NATURE 
467 
SOCIETIES AND ACADEMIES 
Royal Society, February 24.—The President in the chair. 
The following papers were read: ‘‘ Note on certain Lichens.” 
By John Stenhouse. Usnic acid extracted from Usnea barbata 
by dilute solution of carbonate of soda was found to have the 
formula C,, Hj, O,;, and the sodium salt C;, H,; Na O;. This 
result accords with-that of Hesse and differs from that of Knop, 
Rochleder, and Heldt, whose analysis give the formula C,, H),07. 
Usnie acid was also obtained from £vernia prunastri as well 
as evernic acid. Tetrabrom-evernic was got by the action 
of bromine on evernic acid. Its formula is C,, H,. Bry O;. 
The acid extracted from Cladonia rangiferina, though possess- 
ing the same composition as usnic acid, was observed by Hesse 
to have a different melting-point (175° C.) from ordinary usnic 
acid (203° C.) He proposed, therefore, to call it B-usnic acid, 
as it so closely resembled ordinary usnic acid in its general 
character. The author has found that ordinary usnic acid, melting 
at 203° C., obtained from ZLvernia prunastri, Ramalina cali- 
caris, and the various Uszeas, does not yield a trace of B-orcin 
when distilled, whilst, on the contrary, the acid extracted from 
Cladonia, on being subjected to the same treatment, yields 
B-orcin ; thus showing a marked difference in the products of its 
decomposition from ordinary usnic acid, as well as in its melt- 
ing-point. Under these circumstances, therefore, he proposes to 
name the acid from Cladonia rangiferina *‘Cladonic Acid,” 
instead of B-usnic acid, as proposed by Hesse. He intends to 
continue the study of this acid. 
“©On the successive action of Sodium and Iodide of Ethyl 
upon Acetic Ether.” By Prof. Frankland and Mr. B. F. Duppa. 
The authors, referring to a paper by Mr. Wanklyn, wherein it is 
stated that theirinterpretation of the nature of the reaction between 
sodium and acetic acid must be erroneous because it involves 
the disengagement of hydrogen, remarked that Mr. Wanklyn’s 
opinion is founded upon experiments which differ essentially 
from their own, and not warranting the conclusion which he 
has drawn from them. The authors allowed all evolved gas 
freely to escape, while Mr. Wanklyn operated in sealed tubes 
under great pressure. M. L. Cailletet has recently shown that 
the evolution of hydrogen from zine and hydrochloric acid is 
gradually diminished and finally stopped under increasing pres- 
sure, while the evolution of hydrogen from sodium-amalgam and 
water is diminished and finally stopped in a sealed tube. Since 
pressure retards or even interrupts a reaction in which a per- 
manent gas is evolved, whilst it is known to exercise little or 
no influence upon other chemical changes in which no evolution 
of gas takes place, the authors consider this influence of pressure 
affords an explanation of the difference between the results of 
Mr. Wanklyn’s experiments and their own, as regards the evolu- 
tion of hydrogen during the action of sodium upon acetic ether. 
They confirm his observation that sodium dissolves in valeric 
ether, under ordinary atmospheric pressure, without the evolution 
of any gas ; adding that since a reaction, whatever its nature may 
be, which thus proceeds readily with ethylic valerate, can 
scarcely be impossible with its homologue, acetic ether, it is 
probable this reaction goes on side by side with those which 
they have described, but that when the pressure is moderate 
those changes chiefly take place which involve the disengage- 
ment of hydrogen, whilst under the great pressure arising in 
sealed tubes, those changes being more or less suppressed, the 
reaction observed by Mr. Wanklyn comes into prominence. The 
authors reserve their observations upon Mr. Wanklyn’s views 
regarding the changes which take place when sodium acts upon 
acetic, butyric, and valeric ethers, until the publication of the 
experimental data upon which those views are founded. 
Ethnological Society, February 22.—Prof. Huxley, presi- 
dent, in the chair. Mr, E. Backhouse was announced as a new 
member.—By the courtesy of Dr. Lockhart, a calya from China 
was exhibited by Prof. Busk, in illustration of a former paper on 
an ancient calvaria which had been assigned to Confucius. The 
skull is mounted in copper, and was formerly supported on a tripod 
and furnished with a lid.—‘‘ On discoveries of archaeological inte- 
rest in recent deposits in Yorkshire.” By Mr. C. Monkman, of 
Malton. The author described the discovery of worked flints in the 
clay of Kelsea Hill, in the East Riding of Yorkshire. This was 
formerly regarded as belonging to the Hessle clay—a_post- 
glacial deposit unconformable to the true boulder clay of Hol- 
derness—but it is probably only a derivative clay washed from 
the Hessle deposits on Kelsea Hill. It may, therefore, be of 
comparatively recent origin. Large finds of implements of 
Neolithic type are reported to have been made in the York sands. 
Many stone implements have also been found in the old river 
deposits in the Vale of Pickering, chiefly turned up in the pro- 
secution of land-drainage works. The paper was illustrated by 
a fine collection of specimens.— ‘‘On the Natives of Naga, in 
Luzon, Philippine Islands.” By Dr. Jagor. The author described 
in detail the manners and customs of the Bicol Indians who 
inhabit this locality. Dr. Campbell inquired whether there was 
any connection between the name of this place and the Sanskrit 
naga, a snake. 
Entomological Society, February 21.—Mr. Alfred R. 
Wallace, president, in the chair. Professor Schiodte and 
Siebold were elected honorary members. Messrs. B. J. Lucas 
and G. T. Porritt were elected annual subscribers.—Mr. J. 
Hunter exhibited a moth captured in the New Forest, and sup- 
posed to be Plusta ni.—Mr. Albert Miller exhibited galls 
formed in the florets of the tansy by Défterouws larvee.—Mr. 
Pascoe exhibited a beetle from King’s George’s Sound, the 
Nepharis alata of Castelman— Hicketes thoracicus of King, which 
latter name sinks. — Mr. A. G. Butler read a paper ‘* On butter- 
flies recently received by Mr. Swanzy from West Africa.” Three 
new species were described of the genera, Romaleosoma, Philog- 
noma, and Mycalesis. 
. 
London Mathematical Society, February 10. — Prof. 
Cayley, president, in the chair. Mr. A. Ramsay was elected a 
member. The president gave an account (second communica- 
tion) of his paper on “ Quartic Surfaces.”—Mr. Walker made 
some further remarks on the subject of his paper on the ‘* Equa- 
tions of Centres and Foci, and conditions of certain Involutions,” 
read at the January meeting of the society. —The condition that a 
quadric (v) should determine a pair of corresponding points in one 
of the three involutions given by a quartic (z) is the vanishing of the 
cubic invariant of 12 wz. When z and ware the Jacobian and 
quadric covariants of two cubics the preceding condition expresses 
that the two cubics determine an involution. When one of the 
two cubics (v) is the cubic covariant of the other (z) the two 
determine four distinct involutions; and the Hessian of zw de- 
termines the foci in one of the four—viz., that in which the 
points harmonically correspondent are also correspondent in the 
involution. The other three involutions are not analytically dis- 
tinguishable one from another. — Mr. Clifford read a paper 
“On a case of Evaporation in the order of a Resultant.” In it 
he established the two following theorems :—‘‘ Let it be required 
to eliminate x between two equations homogeneous in «x, and 
certain other variables y, z,.... in which equations, however, x 
only occurs in virtue of the occurrence of a quantity 
w=xr yP 2y,... where atBt+y+....=; let, also, m, 2 
be the orders of the equations, and #, & the remainders after 
division of 7 and x respectively by m ; then the order of the 
resultant is 
_mn-hk 
B& 
Theorem 2. ‘‘ Let it be required to eliminate «—-1 variables 
x, y,... from £ equations homogeneous in these and certain 
other variables, in which equations, however, x, y, only occur in 
virtue of the occurrence of £—I quantities 7, v,... all of the 
same order «#; let also mz, #2, ...,. be the orders of the 
equations, and m;= fia + 2i, 4i < mw; then the order of the 
resultant is 
h ” 
Tip (= 2 + jt). 
Mr. Perigal presented to the Society a copy of his *‘ Geometric 
Maps and Contributions to Kinematics.” 
Meteorological Society, January 19.—Charles V. Walker, 
president, in the chair. The Rey. J. Crompton, Dr. C. Fox, 
and Mr. E. J. Sykes were elected Fellows. The following 
papers were read ; ‘‘On the Temperature and Humidity of the 
Air at the Heights of 22 feet and 50 feet above the ground, in 
comparison with the Temperature and Humidity of the Air at 
the Height of 4 feet.” By Mr. Glaisher. Our knowledge of the 
temperature and humidity of the air near the surface of the 
earth is almost entirely confined to within 4 or five feet above 
the earth. The theory that the temperature was always lower 
at higher elevations was proved not to be at all times true, and 
the theory of the decline of 1° of temperature in every increase 
of 300 feet of elevation, was proved to be erroneous. The 
author stated the results of his observations in the great Captive 
Balloon, at Ashburnham Park, Chelsea, which M. Giffard 
