Fan. 12, 1882] 
NATURE 
251 
ult. At Calcutta it lasted about two minutes. It was especially 
severe in Madras, where, judging from the space devoted to it 
by the local papers, it would appear to have caused much alarm. 
No damage is, however, reported. 
THE English representative of the company which manu- 
factures the Griscom motors, mentioned in our article last week, 
writes us to. the effect that the small form of motor there de- 
scribed will attain a speed of 3000 revolutions per minute when 
worked with a 6-cell bichromate battery, and will accomplish 
1000 foot-pounds of work per minute ; and that with a dynamo- 
current this limit is far exceeded. We are also informed that 
the Company has established a branch in London for the direct 
supply of their motors to the public. 
Dr. WOEIKOFF asks us to correct an error in the abstract of 
his paper on the freezing on a salt lake (NATURE, vol. xxv. 
p. 206). It is there stated that ‘‘it was never observed hefore 
in laboratories that salt water was cooled below — 4° without 
being frozen, and here we have salt water remaining unfrozen at 
—13° below zero.” In the paper referred to Dr. Woeikoff 
simply stated that temperatures below — 4° C. were not before 
observed in saline solutions outside of laboratorie-, while here 
we have temperatures of — 13° observed in a salt lake. 
THE additions to the Zoological Society’s Gardens during the 
past week include a Crab-eating Raccoon (Procyon cancrivorus) 
from South America, presented by Mr. H. B. Whitmarsh ; two 
Pileated Jays (Cyanocorax fileatus) from La Plata, presented by 
Mr. C. S. Barnes ; two Lesser Black-backed Gulls (Lavws fuscus), 
British, presented by Mrs, Brindley; a Speckled Terrapin 
(Clemmys guttata) from Massachusetts, three Confluent Rattle- 
snakes (Crotalus confiuentus) from Dakota, U.S., presented by 
Mr. W. A. Forbes, F.Z.S.; a Blue-eyed Cockatoo (Cacatua 
opthalmica) from the Solomon Islands, a Short-eared Owl (Asio 
brachyotus), British, deposited; six Grey Squirrels (Sciurus 
cinereus var, nigra) from North America, purchased ; a Gayal 
(Bid0s frontats), born in the Gardens. 
THE SWISS SEISMOLOGICAL COMMISSION 
~HE Seismological Commission of Switzerland, after having 
published in French and German an excellent text-book on 
earthquakes, by Prof. A. Heim, and after having widely circu- 
lated its queries on earthquakes, has received a great mass of 
information which is mentioned in high terms both as to their 
accuracy and interest. Prof. A. Heim, availing himself of this 
material, has already published in the Axnwaive of the Physical 
Observatory at Bern, an interesting monograph on the earth- 
quakes of last year, and now M. Forel, of Morges, also pub- 
lishes in the Archives des Sciences Naturelles of Geneva a first 
paper on earthquakes for the first thirteen montbs of the 
existence of the Commission from December, 1879, to January, 
1881. We see, from a list of earthquakes during the years 1876 
to 1880, which he publishes, that there were in Switze:land 
during this period of time, no less than forty-eight ear:hquakes, 
of which twenty-five were in 1880, the Commission having re- 
ceived accurate information on twenty-one of them, and four 
feeble shocks more having been reported in newspapers, but 
they still are rather doubtful. This increase of earthquakes in 
1880 must, however, be to a certain degree the result of more 
accurate observation since the appointment of a special Com- 
mission for that purpose. The chief earthquakes during these 
thirteen months—December, 1879, to January, 1880—were the 
following :—On December 4 and 5, 1879, consisting of three 
toain shocks and of seven feebler ones. The first and the third 
of the main shocks had each an extent of about 100 miles, and 
the aggregate area shaken by these earthquakes had a length cf 
250 miles and a width of 40 miles, its longer axis being parallel 
to the main chain of the Alps; the centres of the successive 
shocks advanced from south-west to north-east. 
The earthquake cf December 29 to 31, 1879, had a great 
extension. ‘To use M., Forel’s expression, ‘‘ this beautiful earth- 
quake” consisted of three chief shocks and of a dozen smaller 
ones, ‘The first strong shock was experienced on an area limited 
_ extension. 
by Lyons, Locle, Solothurn, Luzern, Sion, Chamonix, and 
Annecy, affording thus an ellipse 200 miles long and 100 miles 
wide, the great axis of which also was parallel to the main 
chain of the Alps. Its centre was between the Arve and Drarse 
Rivers, and its intensity at Geneva reached seven degrees of the 
decimal scale proposed by M. Forel. The shock propagated 
itself by several oscillations, at a speed of 300 to 400 metres per 
second. The following main shocks had a smaller area, but 
the centre did not advance along the axis of the shaken area ; it 
remained in the neighbourhood of Geneva. It is rather remark- 
able that at the same moment as Savoy and Western Switzerland 
experienced this earthquake, another series of feeble shocks was 
felt at Niederaach in Thurgau, both earthquakes being sepa- 
rated by a zone 160 miles wide, where no shocks were observed. 
The earthquake of July 3 to 5, 1880, extended throughout the 
whole of Switzerland, reaching also the southern parts of the 
Grand Duchy of Baden and Northern Piemont, and shaking ar 
area 203 miles long and 187 miles wide. It was much compli- 
cated, two strong shocks having been felt almost in all Switzer- 
land, whilst many other feebler shocks, about twenty in number, 
which preceded and followed the main ones, had a merely local 
Prof, Heim shows that in this earthquake there was 
no central point from which the shocks might have been tran- 
smitted in all directions ; and he thinks therefore that there was 
a general dislocation of strata ona very wide surface, rather than 
any shock departing from any determined point of the territory. 
After further details, M. Forel tries to classify the earthquakes 
with relation to the seasons, and to the position of the moon ; 
but we will not follow him in these researches, as he himself 
states that a thirteen months’ period of observations is too short 
atime for such generalisations. But we may notice the circum- 
stance that, whilst in some earthquakes the shock is propagated 
from a centre to the circumference, in others all the surface of the 
country seems to be pushed in one general direction ; Prof. 
Heim discovers this character in the earthquakes of December 
5, 1879, and of July 4, 1880, The importance of this remark 
will not escape the attention of those who are eagaged in the 
study of the formation of mountain ridges. 
It is obvious that the Commission met with several difficulties 
in performing their task, and the chief are in the notation of the 
time of the earthquake and of its direction. Humanity seems 
to be, even in the fatherland of clockwork, very far from know- 
ing the true time, and even the clocks of the towns, of the rail- 
way and telegraph stations, seem to leave very much to desire as 
to the accuracy of the information they give us. Some im- 
provement, however, is shown in that direction during this Jast 
year, and it may happen that the desire of making accurate 
observations on earthquakes will give an impulse to some im- 
provement in our knowledge of time. As to the direction of 
earthquakes, there are yet more difficulties, and M. Forel points 
out the interesting circumstance that nearly all information as to 
the direction of earthquakes is influenced by the orientation of 
streets, the direction of earthquakes nearly always being given 
either parallel or perpendicular to the observer’s street. On 
some occasions, as in the earthquake of July 28, 1881, every- 
thing on tbe surface of the soil seems to be in a vibratory 
motion, as grains of sand on the surface of a vibrating slab, and 
the shocks are observed in all possible directions as well vertical 
as horizontal, 
But it is not only from Switzerland that the Seismical Com- 
mission has received valuable information, and we find in the 
Archives two interesting papers on the earthquakes of the island 
of Chio, by M. Arland, and on those in Asia Minor, by M. van 
Lennep. As to the former, we notice that the volcanic eruptions 
on the island of Nisyros had ceased a month before the 
catastrophe, and that they have not begun again up to the pre- 
sent. ‘The oscillations of April 3 seem to have had an amplitude 
of 15 degrees, and from April 3 to April 7, there were counted 
no less than 250 shocks, of which 30 to 40 were very strong. 
On April 11, at 7 p.m., there were the well-known great shocks 
which occasioned such a panic, They continued until the month 
of August, being followed by a standstill from August I to 
August 25. On this day and the following there were again 
strong shocks. From a complete list of houses destroyed, pub- 
lished by M. Arland, we see that there were no less than 6730, 
and that the number of killed and wounded was, in various 
villages, as much as 10 to 30, and even 36 per cent. of the 
population, M, Arland gives also some interesting notices as to 
the direction of the shocks in Calimassia, and to the disturbances 
they have done to the walls of the houses, 
