40 
NWA LORE 
| NoveMBER 8, 1906 
caleium carbonate there is a fairly definite temperature, 
470°+3° C., at which arragonite passes into calcite, but 
the change in this case is not reversible, and even at low 
temperatures calcite appears to be the stable, and 
arragonite the labile, form. 
Messrs. F. Darton anpd Co., Clerkenwell Optical 
Works, have sent us a copy of the latest issue of their 
list of electrical novelties. The catalogue may be com- 
mended to the attention of those who are interested in 
the application of electricity to domestic, medical, and 
other purposes. 
Messrs. F. E. Brecker anp Co., Hatton Wall, London, 
have submitted for our inspection a specimen of their 
““Nivoc ’’ patent stencil. 
young students of science in making drawings of appar- 
atus, and will be found of service for this purpose. At 
the same time, the adoption of stencils of this kind will 
deprive pupils of the practice necessary to enable imem 
to develop the power of rapid, unaided sketching which, 
as Huxley long ago pointed out, is essential to the student 
of science. 
The stencil is designed to assist 
A sECOND edition of Prof. A. E. H. Love’s ‘* Theoretical 
Mechanics. An Introductory Treatise on the Principles of 
Dynamics,”’ has been published by the Cambridge Uni- 
versity Press. The first edition of the work was reviewed 
at length in our issue for June 23, 1898 (vol. Iviii., p. 169). 
It is only necessary to state that the changes which have 
been made in the present edition are, for the most part, 
of the nature of a re-arrangement of the order of the 
material. The consequence is that the theory has been 
presented in a less abstract fashion, and long preliminary 
discussions have been avoided. 
A. seconp edition of the late Prof. P. Drude’s ‘‘ Lehr- 
buch der Optik’? has just been published by Mr. S. 
Hirzel, Leipzig. The text has been revised, and forty 
pages have been added to the book in order to bring under 
consideration the work in magneto-optics and related sub- 
jects done since the original edition appeared six years 
ago (see Nature, October 18, 1900, vol. Ixii., p. 595). 
The manuscript of the new edition was completed and 
partly printed before Prof. Drude’s lamented death, but 
Mr. F. Kiebitz has seen it through the press. The work 
has now an index. 
Tue twelfth volume of the new series of the Reliquary 
and Illustrated Archaeologist has now been published by 
Messrs. Bemrose and Sons, Ltd. It consists of the four 
quarterly numbers issued during the present year. The 
first of these parts includes a contribution by Mr. J. 
Patrick to the series of papers dealing with the sculptured 
caves of East Wemyss, in which the Factor’s Cave is de- 
scribed. The April number contains an illustrated article 
by Mr. R. Quick entitled ‘‘ Notes on the Evolution of the 
Means of Transport by Land and Water.”? The most 
primitive means of transport by land is stated to be by 
means of tent poles and skin tents, but it would be hard 
to prove that this method was primitive either in time 
or in culture, especially as the author credits ‘* prehistoric 
man ”’ with “‘a conveyance of logs of wood bound together 
by withes and carried in the hand, somewhat in the 
manner of the Chinese sedan chair.’’ The July number 
includes two interesting papers by Mr. J. Charles Wall on 
Lastingham; one, ‘‘ Pure Norman,”’ describes the unique 
example of a pure Norman crypt, free from any in- 
trusions of later architecture, and the other, ‘‘ Lasting- 
ham Relics,’’ tells of some of the treasures, mainly the 
NOMMO 32, aVOL. 75) 
sculptured stones, to be found in the crypt. The con- 
cluding part is perhaps of less interest to the man of 
science. It contains, with other papers, an account by 
Charlotte Mason of the characteristics of Blythburgh and 
its church, and a short paper by Sophia Beale on the 
evolution of the ancient lamp. 
OUR ASTRONOMICAL COLUMN. 
Tue Caroriric Rapration oF THE SuN.—Further results 
relating to the intensity of the solar calorific emissions 
are published in No. 17 of the Comptes rendus by MM. 
Millochau and Féry. Using the instrument described in 
their former note, and considering only the centre of 
the solar disc, they obtained measures at Meudon (alti- 
tude=150 m.), Chamonix (altitude=1030 m.), and the 
summit of Mont Blanc (altitude=4810 m.). Accepting the 
emissive power as being equal to unity, these gave 4820°, 
5140°, and 5560°, respectively, when standardised by the 
electric furnace. All these measures were obtained when 
the sun was near the zenith, and the observers give a 
table showing the hourly variation of the apparent 
temperature from 8 a.m. to 6 p.m. 
The maximum observed temperature on the summit of 
Mont Blane was 5590° absolute, and, roughly correcting 
for the atmospheric absorption, this gives the final result 
as 5620° absolute. 
THE SystEM or 61 CyGni.—In No. 4128 of the Astro- 
nomische Nachrichten Prof. Barnard discusses a series of 
measures of the double star 61 Cygni which he made on 
144 nights between August 7, 1900, and November 12, 
1904. These measures were undertaken for the purpose 
of testing Dr. Wilsing’s hypothesis as to the existence of 
an unknown dark body in the system of this star. This 
observer found that his photographic measures indicated 
an apparent periodic oscillation, in the distance between 
the two components, of about o”-3, taking place in twenty- 
two months. If this oscillation were real its effect on 
the measures of the parallax of this star would be con- 
siderable, and might account for the large differences 
already obtained by various observers. 
Prof. Barnard’s results do not, however, confirm the 
hypothesis, although the observations extended over twice 
the interval of Dr. Wilsing’s supposed period. The dis- 
tance between the two components does not appear to be 
affected by any periodical variation, and only in one case 
does the distance difference exceed the mean by so much 
as one-tenth of a second of arc. It seems evident, there- 
fore, that some cause other than that of a disturbing 
body will have to be found for the differences observed 
by Dr. Wilsing. 
Tue Care Opsrervatory.—In his report of the work per- 
formed at the Cape Observatory during the year 1905, Sir 
David Gill states that the two underground azimuth-marks 
of the new transit circle are now working satisfactorily, 
and that the observations with this instrument show a 
systematic diurnal variation of azimuth amounting to 
about +0-02 second. When the observations of circum- 
polar stars are sufficiently discussed to determine the 
absolute variation of the azimuth-marks, it seems possible 
that these may prove sufficiently stable to permit of the 
determination of the horizontal component of Prof 
Chandler’s change of latitude. The automatic arrange- 
ments for regulating the pressure and temperature inside 
the sidereal clock-case are now perfect, the temperature 
never varying from 75° F. by more than one-tenth of a 
degree. The work for the Astrographic Chart and Cata- 
logue was nearing completion at the end of 1905, and 
during that year 148 catalogue plates, containing 1944 
standard and 112,086 other star images, were measured. 
Minor Pranets.—In No. 4128 of the Astronomische 
Nachrichten Dr. Bauschinger publishes the numbers which 
have been allotted to the recently-discovered minor planets. 
From this list we see that the total number, up to June 
21, 1906, was 601, and that thirty-two new ones were dis- 
covered between July 30, 1905, and that date, mostly at 
the Heidelberg Observatory. The same publication also 
contains a list of the names allotted to various minor 
planets between No. 459 and No. 562. 
