Dee. 8, 1881] 
internal, to be the Schizomycete Leftothrix buccalis, the mode 
of entry and propagation and the life-history of which he 
follows out in detail, The acids which occur in the mouth, 
especially lactic acid, while they may greatly promote the decay, 
cannot give rise to it. The Leptothrix can be readily recognised 
by its iodine reaction, The author considers further that in many 
cases diseases of various parts of the body can be distinctly traced 
to excretions from the mouth and teeth. Other observers had 
already traced a connection between decayed teeth and septic 
abscesses, in which was found a fungus similar to that which 
occurs in decayed teeth. 
THE balance has been applied by Herr v. Jolly, at Munich, 
to the problem of gravitation. thus (Wied. Ann, No, 10): The 
instrument was placed in the upper part of a tower, and from 
each of theascales depended a wire (through a zinc tube) having 
a second scale at the lower end, 21005 m. below. These lower 
scales were I1’02m, from the ground, so that a lead ball one 
metre in diameter might be brought under one of them. A body 
brought from an upper scale into a lower one has an increase of 
weight corresponding to its degree of approach to the earth’s 
centre and to the increase of acceleration. When the lead ball 
is brought under the same lower scale its pullis added. The 
difference of the increments of weight, with and without the lead 
ball, indicates the amount of pull of the latter, and the quotient of 
this pull and that of the earth alone furnishes a means (with the 
law of gravitation) of comparing the density of the earth with 
that of the lead, and, the latter being known, of determining 
the mean density of the earth. Referring to the original for 
details, we merely state that the author fiads the mean density 
5°692 (probable error not more than + 0068). This agrees 
more or less with other determinations ; from the mean of those 
with the torsion balance it diverges about 2 per cent. 
THE death is announced, at the age of eighty-nine years, of 
Jean Alfred Gautier, the doyen of science in Geneva, and one 
of the most active citizens of that city. M. Gautier belonged to 
a very old Genevese family, and displayed an early taste for 
science. In Paris he counted among his teachers such men as 
Laplace, Lagrange, Legendre, and Poisson, and in England he 
formed a life-long friendship with Sir John Herschel. When 
he settled down in. Geneva from his travels, he carried on the 
work of the little observatory then existing at Geneva, and it 
was through his exertions that a much better one was built, 
though defective vision did not enable him personally to super- | 
intend it. M. Gautier was one of the earliest to discover a rela- | 
tion between sun-spots and terrestrial magnetism, and in many | 
ways he laboured successfully to advance science in his native | 
city. 
WE learn also of the death of Dr. Chr. G. A. Giebel, 
Professor in the Philosophical Faculty at Halle University, an 
eminent zoologist and geologist. He died at Halle on Novem- 
ber 14. The death is also announced, on November 11, of Prof. 
Engelhardt, a well-known Danish antiquarian, and secretary of | 
the Society of Antiquaries at Copenhagen ; and of Prof. Paul- 
Giinther Lorentz, a well-known German authority on mosses 5 
he died at Concepcion del Uruguay at the early age of forty- 
six years. 
THE earthquake of November 18 was noticed in Switzerland, | 
shocks being reported from Ragatz and St. Gall. A great area, 
comprising Westphalia, Hessen-Nassau, and Belgium, was also 
' visited by thiS phenomenon ; it was noticed at Miinster, Marburg, 
Brussels, Tournai, and Liége and Metz. On November 24 at | 
II p.m. a shock was observed at Dedenborn, near Montjoie 
(Rheuish Prussia), and two shocks at Pergine (Southera Tyrol) 
early on November 20. 
In February next a private scientific exploring tour to Persia | 
will be undertaken by a Viennese medical man, Dr. Polak. He 
NATURE | 
137, 
will lead the expedition himself, and will be accompanied bya 
geologist and a botanist. All expenses will be defrayed by 
Dr. Polak. 
Most of the members of the Royal Commission on Technical 
Instruction have returned to England; they have, we under- 
stand, accumulated a mass of valuable information in the course 
of their preliminary tour, which has included the principal centres 
of industry in France. 
THE dinner in commemoration of the- Brewster Centenary 
will take place in Edinburgh to-morrow, 
Pror. J. G. McKenprick has been appointed Fullerian 
Professor of Physiology for three years at the Royal Institution. 
THE Vienna Geographical Society will celebrate the twenty- 
fifth anniversary of its foundation on December 12 and 13 next. 
WE have received from the Parkes Museum a copy of the 
artistic certificate of awards in connection with the International 
Medical and Sanitary Exhibition, lithographed from the original 
design by Mr. Cave Thomas. The certificates are now being 
distributed. The following facts are of interest :—Exhibitors 
from different parts of the United Kingdom, 414; exhibitors 
from abroad, 88; making a total of 502 exhibitors, of whom 
258 received either awards of the first class, or awards of merit. 
A suRVEY party, under Col. Branfil, has left Calcutta for the 
purpose of verifying and completing the survey of the Megin 
Archipelago. The work, including the measurement of the 
base line, is expected to occupy about six months. Dr. Anderson, 
Superintendent of the Indian Museum, has accompanied the 
party and will take the opportunity of instituting a thorough 
investigation of the local fauna. 
TueE German Government contemplates sending out two expe- 
ditions for observing the transit of Venus in 1882: one to the 
mouth of the La Plata River, the other to Magelhaen’s Straits or 
the Falkland Isles. The expedition of 1874 cost the Government 
600,000 marks (30,000/.), the one of next year is estimated to 
cost only 195,000 marks (9750/.). 
M. Moucuez, director of the Paris Observatory, is making 
arrangements for taking meteorological observations at an eleva- 
tion of 2300 metres by means of a captive balloon, The balloon 
will be charged with ordinary coal-gas. These ob:ervations are 
| intended to facilitate the calculation of atmospheric refractions. 
Durinc November, twenty-two earthquake shocks have been 
observed in various parts of Switzerland. They seem to have 
been most numerous in the neighbourhood of Schaffhausen, 
A.INE monument has been erected at Bonn oa the tomb of 
the eminent geologist, Prof. Jakob Noggerath, who died on 
September 13, 1877. The sculptor is Herr Aloert Ktipper. 
THE preliminary earthworks for the erection of the monument 
in memory of Justus von Liebig have been begun on the Maxi- 
miliansplatz at Munich, 
M. TIsSANDIER has organised a private company to prosecute 
his experiments with an electric directing balloon. 
Some of our readers may be glad to know that King’s Col- 
leze, London, has a Science Society which meets on Wednes- 
days at § p.m, during term, for the purpose of reading papers on; 
and for the discussion of, scientific subjects. The papers, we 
are glad to learn, are generally experimentally illu trated, 
Dr. TAYLOR, curator of the Ipswich Museum, was on Saturday 
afternoon presented with a purse of 660/., accompanied with a 
handsome clock and gold watch for Mrs. Taylor, in recognition 
of his labours in connection with the museum, and of his annual 
course of scientific lectures, which for a number of years he has 
delivered in Ipswich without any emolument. Sir Richard 
