DECEMBER 10, 1896] 
NATURE 
135 
‘formed a separate group messing together in the same sheds. Of 
‘these, 30 were inoculated and 16 left ; of the 16 uninoculated, 
11 developed cholera and died ; among the 36 there was only 
‘one case, but this terminated fatally. There seems to be no 
room for doubt that if all the coolies had been inoculated at the 
-outset the disease would have ceased in a few days. 
THE Maryland Geological Survey, in an endeavour to make 
its work fundamental, and at the same time of the greatest 
value to the material interests of the State, has taken up, in its 
preliminary investigations, a thorough study of the magnetic 
-conditions affecting that portion of the earth’s crust within the 
borders of Maryland. In addition to the importance of this 
work upon the future observations and determinations of the 
great rock-masses contained within the State, these investiga- 
tions will be of immediate practical benefit to all land surveyors, 
and from that standpoint alone justify the undertaking. We 
~ dearn from an advance sheet from Zervestrial Magnetism that 
the investigations are being conducted by Dr. L. A. Bauer, 
undgr the direction of the State Geologist, Prof. W. Bullock 
Clark. The Survey will ultimately average one station to about 
140 square miles, thus equalling in detail that of Riicker and 
‘Thorpe in the British Isles. There is probably no State in 
America that presents, within so small an area, such a variety of 
geological formations as Maryland. It is then peculiarly fortu- 
mate that a detailed magnetic survey has been undertaken in 
this State, and simultaneously and in connection with the 
Geological Survey. It is hoped that other States will soon 
follow the example set by Maryland. 
AY a recent meeting of the Otago Institute, Mr. G. M. Thom- 
‘son exhibited some interesting fossil remains obtained from a 
mining claim at St. Bathans. The fossils occurred in a bed of 
hard clay which was overlaid by 30 feet or 4o feet of lacustrine 
(marine?) clays. They consist of leaves and fruit capsules of a 
species of Hakea. The genus Hakea belongs to the order Pro- 
‘teaceze, and is at present confined to Australia, where about 100 
species are known. Of these sixty-five have only been found 
hitherto in West Australia. The occurrence of the genus in 
New Zealand in Tertiary times is of great interest in its bearing 
-on questions of geographical distribution. 
AmonGsT the things recently exhibited at the opening meeting 
-of the Geologists’ Association and at the ‘‘at home”’ of the 
‘Geological Society, one that deserves attention was shown by 
the Geological Photographs Committee of the British Asso- 
‘ciation. Several portfolios were exhibited which contained the 
prints recently acquired by that body, among them being a fine 
set of views of the Yorkshire Coast taken- by Mr. Bingley, a 
large series of small photographs taken during the recent re- 
examination of Charnwood Forest by the Geological Survey, 
and some most useful prints showing the chalk of Beer and the 
Jandslips of that neighbourhood, taken several years ago by Sir 
Henry T. Wood. The whole collection, now numbering about 
1400 photographs, is lodged in the library of the Jermyn Street 
Museum, where it is borne company by the Survey collection of 
\prints taken and acquired by the officers of the Geological Survey, 
‘the two collections supplementing one another. Although so 
much has been done, the labours of the Committee are by no 
means over, and many parts of Britain still need to be surveyed 
‘by the camera. Many local bodies have given ready aid to the 
work, and they must still be looked to to watch for phenomena 
which ought to be registered, and to help in keeping the 
collection up to date. It.is hoped that this may come to be a 
recognised part of the work of local societies. and no pains are 
being spared to enlist the services of new societies, and to 
-encourage those which have begun, to continue in their good 
work. Among the districts scarcely, if at all, represented at 
present in the collection are the following :—Bedford, Bucks, 
NO. 1415, VOL. 55] 
Berks, Cambridge, Cumberland, Essex, Gloucester, Hants, 
Hereford, Herts, Huntingdon, Lincoln, Middlesex, Monmouth, 
Norfolk, Northants, Nottingham, Oxford, Rutland, Stafford, 
Suffolk, Surrey, Sussex, Warwick, Westmoreland, Wiltshire, 
Worcester, South and Central Wales, Scotland, except parts of 
the Highlands and of the Central Valley, S.E., S.W., W., and 
Central Ireland. It is true that some of these districts do not 
lend themselves so well as others to this method of illustration, 
but what work there is should be done without delay. There 
will thus be got together a set of illustrations which will be a 
most valuable addition to published maps, sections, papers, and 
memoirs, and one which will in many respects remedy the 
deficiencies and supply the omissions of the methods of illustra- 
tion usually employed. 
Pror. E. VILLAR describes (4 ¢t72 dec Lincez, v. 8) some fresh 
experiments relating to the property possessed by Rontgen rays 
of inducing in gases the power of discharging electrified bodies. 
This power is found to persist for a certain time after the rays 
have ceased, and it is not altogether destroyed, although con- 
siderably reduced, by causing the gases to flow through a tube 
several metres long. Sparks from an induction coil, whether 
reinforced by a condenser or not, are found to impart the same 
discharging power to gases, and their etficacy in either case 
increases at first with the length of the spark ; but after a certain 
length of spark has been exceeded, the efficacy without the 
condenser decreases to zero. Another series of experiments on 
the electrostatic dispersion of Rontgen rays is described by Dr. 
Uno Panichi (ARévzs/a Scéentifico-Industréale), who examines the 
question of whether Réntgen rays are emitted from a Crookes’ 
tube after the discharge within the tube has ceased. Dr. 
Panichi finds that within 1/50 of a second from the termina- 
tion of the discharge, the Crookes’ tube has no effect whatever 
on an electroscope, so that any after-effects which may be 
observed in other experiments must be due to the afore- 
mentioned modifications in the air which has been traversed 
by the rays. 
Tue January number of Sczence Progress, which now appears 
quarterly and in an enlarged form, will contain important and 
interesting articles on ‘‘ Liquid Crystals,” by Prof. H. A. 
Miers, F.R.S., Professor of Mineralogy in the University of 
Oxford ; on ‘‘ Selection in Man,” by Dr. John Beddoe, F.R.S.; 
on “The Glossopteris Flora.” by A. C. Seward, Lecturer on 
Botany in the University of Cambridge ; on ‘* Condensation 
and Critical Phenomena,” by Dr. E. T. Kuenen. 
A COMPLETE list of the scientific writings of the late Prof. 
Adolfo Bartoli has been compiled by Dr. Carlo del Lungo, 
and is published in the Aéésta Scéentifico-Industrtale for August— 
October 1896. 
From Profs. Elster and Geitel, we have received a copy of 
their important paper, published in the current volume of 
Wiedemann’s Annalen (pp. 487-496), on the photo-electric 
after-effects of kathodic rays. 
Tur snakes found within fifty miles of New York City are 
enumerated by Mr. R. L. Ditmars, with brief descriptions of 
the species, and notes on their local distribution and habits, in 
an ‘‘ Abstract” (No. 8) of the Proceedings of the Linnean 
Society of New York. 
Tue Deutsche Seewarte has issued the seventh volume of 
Ueberseeische meteorologische Beohachtungen, containing actual 
readings and monthly results of various stations in distant parts 
of the globe. The observations in Labrador are especially 
interesting to students of weather sequences which may affect 
this country, as many areas of low barometric pressure between 
Canada and the North Atlantic Ocean take their course over 
that peninsula. In addition to four stations in Labrador, the 
present part contains observations from Walfish Bay, Samoa, 
