470 
NATURE 
| March 15, 1883 
mission of air to the lungs. The vaso-dilator nerve centres 
(sudorific and respiratory) are excited directly by superheated 
blood, 
AN interesting trial of an electrically-moved tramcar took 
place on Monday at Kew, and, notwithstanding some inevitable 
hitches, may be regarded as fairly successful. The peculiarity 
of the application of electricity in the present case lies in the 
use made of accumulators. The car was constructed at the 
Electrical Power Storage Company’s works at Millwall, and is 
of the usual dimensions for carrying forty-six inside and outside 
passengers. It weiyhs, with its accumulators and machinery, 
but without any passengers, four and a half tons. Under the 
inside seats of this tramcar is placed the accumulator, consisting 
of fifty Faure-Sellon-Volckmar cells, each measuring 13 inches 
by 11 inches by 7 inches, and each weighing about 80 lbs. This 
accumulator, when fully charged, is capable of working the 
tramear with its maximum load for seven hours, which means 
half a day of tramway service. From the accumulators the 
current is communicated by insulated wire to a Siemens’ 
dynamo placed underneath the car, which acts as a motor, the 
motion being transmitted to the axle of the wheels through a 
driving-belt. To start the car the current is switched on 
from the accumulator to the dynamo, the armature of which 
being set in motion, the power is communicated to the driving 
wheels, The car can be driven from either end, and the power 
required can be exactly appor.ioned to the work to be done by 
using a greater or lesser number of cells. Ona level road, for 
instance, with a light load, only a comparatively small number 
of cells will be necessary, but with a heavy load or on a rising 
gradient greater power will be required, and additional cells 
must be switched in. The action of the motor, and consequently 
the direction of the car, can be readily reversed by reversing the 
current, and the car can also be as readily stopped by shutting 
off the current entirely and applying the handbrake with which 
the car is fitted. At night the car is lighted by means of four 
Swan incandescent lamps, two of which are placed under tie 
roof and one at each end of the car. All the lamps derive their 
current fro. the accumulator. The car is also fitted with electric 
bells, worked from the same source, and is to be run regularly 
on the Acton tramway line, The Storage Company also had a 
successful trial on Monday at Kew of a launch fitted with a 
battery of forty cells and a Siemens’ dynamo. 
WE learn from the last number of the ¥ozsa/ of the Russian 
Chemical and Physical Society (1883, fascicule 1) that, at a 
recent meeting of the Society, Prof. Mendeléeff made a commu- | 
nication on the applicability of the third law of Newton to the | 
mechanical explanation of chemical substitutions, and especially 
to the expression of the structure of hydrocarbons. If we admit 
not only the substitution of hydrogen by methyl, but also the 
substitution of CH, by H,, and of CH by H,—as must be 
according to the law of substitutions as deduced from the third 
law of Newton—we can not only explain, but also predict, all 
cases of isomerism, without recurring to the usual conceptions as 
to the connections and atomicities of elements. Thus, benzene 
can be understood as a normal butane, CH,CH,CH,CHg, or 
(CH;CH,)., where a double symmetrical substitution of H, by 
CH has taken place, the H, having been taken from CH, and 
the third H from CH,, so that only the CH groups are left; 
CHCH \? 
CH . 
of benzene, diproparzyl the formation from acetylene, and the 
substitution and addition products from benzene. 
benzene being thus =(( It would explain the isomer 
THE additions to the Zoological Society’s Gardens during the 
past week include a Rhesus Monkey (MJacacus erythreus é) 
from India, presented by Mr. C. F, Henshaw ; a Grey Ichneu- 
mon (/ferpestes griseus) from India, presented by Mr. F. C. H. 
Dadswell; a Herring Gull (Zarus argenta/us), British, pre- 
sented by Miss Ella Vicars ; three Common Swans (Cygnus olor), 
British, presented by Mr. J. Hargreaves; four Prairie Grouse 
(Zetrao cupido) from Iowa, North America, presented by Mr, 
Henry Nash; a Daubenton’s Curassow (Crax daubentoni 2) 
from Venezuela, presented by Mr. Rowland Ward, F.Z.S.; a 
North American Turkey (AZée/eagris gallo-pavo 6) from North 
America, presented by His Grace the Duke of Argyll, K.T., 
F.R.S. ; a Malbrouck Monkey (Cercopithecus cynosurus) from 
West Africa, deposited ; a Gaimard’s Rat Kangaroo (Aypst- 
prymnus gaimardi @), three Coypu Rats (AZyopfotamus coypus), 
born in the Gardens. 
GEOGRAPHY OF THE CAUCASUS 
OF the several branches of the Russian Geographical Society, 
the Caucasian and the East Siberian are well known for 
the amount of valuable geographical work they have done during 
the thirty years or so of their existence. The high scientific interest 
connected with the exploration of the Caucasus is obvious. The 
scientific exploration of the Alps has revealed to us anew world ; 
but the highlands of the Caucasus, with the high plateaux of 
Trauscaucasia, afford a still greater variety of geological and 
physico-geographical features than the Alps ; besides, situated 
as they are on the boundary between the moist climate of the 
west and the dry one of the east, between the deeply-indented 
coasts of Europe and the deserts and plateaux of Asia, between 
the young civilisations of the west and the old civilisations of the 
east, the Caucasian highlands afford such a variety of climatic, 
botanical, zoological, and ethnological features as hardly can be 
met with in any other country of the world. Very much remains 
to be done to bring these highlands within the domain of 
scientific knowledge. In what has been done up to the present, 
the Caucasian branch of the Russian Geographical Society has 
always had a good share, either by direct exploration, or by 
bringing to the knowledge of the scientific world such explora- 
tions as otherwise would have remained unknown in the archives 
of different Government offices, or by giving a scientific cha- 
racter to such explorations as were made for military or 
diplomatic purposes. Besides, the activity of the Caucasian 
Geographical Society is nct limited to the Caucasus. Closely 
connected with the General Staff of Tiflis, it extends its explora- 
tions to the Trans-Caspian region, to Asia Minor, and to Persia ; 
and closely follows the Russian military expeditions, surveyors, 
and diplomatists who eagerly visit these countries. 
Unfortunately the publications of the Caucasian branch—the 
Zapiski or Memoirs, and the Jzvestia or Bulletin—are but very 
insufficiently known abroad, Fetermann’s Mittheilungen being 
nearly the sole channel through which they are brought to the 
notice of the scientific world. The following summary, therefore, 
of the last publications of the Society will be of some use to 
scientific geographers. Without attempting to review all the 
volumes of the Memoirs and /zvestia which have appeared, we 
shall limit this paper to a review of the tw» last of each, the 
chief results of the papers contained in former volumes being 
already embodied in Elisée Reclus’s ‘‘Géographie Universelle.” 
Several papers of the sixth volume of the /zvestia are devoted 
to the geodesy of the Caucasus and adjacent countries. During 
the war of 1878 a considerable amount of geodetical work was 
, done in the province of Kars and in Asia Minor, and M. Kul- 
berg gives the latitudes and longitudes determined. The longi- 
tudes of Kars, Erzerum, and Mysun were determined by means 
of telegraphic signals (the accuracy of this method being such as 
to reduce the probable error between Pulkova and Vladivostok, 
on the Pacific, to 014, that is, to 50 yards on a distance of 
7000 miles). Other longitudes were determined by chronometer. 
A trigonometrical network was extended to Erzerum, and 
numerous surveys were made. The longitudes of several points 
, at Constantinople were determined with great accuracy by 
General Stebnitzky, as well as that of Batum by M. Kulberg. 
The same volume contains also a list of latitudes and longi- 
tudes determined on the banks of the Emba and on the Mangi- 
shlak peninsula.—M. Kulberg contributes also an interesting 
paper on the results of determinations of lengths of the pendulum 
on the Caucusus, in order to determine the increase of gravity 
caused by the Caucasian chain. The observations were made at 
