NOVEMBER 12, 1903] 
Assiniboia, Saskatchewan, Alberta, and Athabasca, and 
across British Columbia to the neighbourhood of Port 
Simpson. In aid of this enterprise a concise report on the 
resources of the line of country between Quebec and Winni- 
peg has been drawn up by Dr. H. M. Ami, of the Geological 
Survey of Canada (Sessional Paper, No. 143). The physical 
geography, geology, soils and economic minerals, and the 
natural history generally are described. 
IN some notes on the geology of the Hawaiian Islands 
(Amer, Journ. Science, October), Mr. J. C. Branner directs 
attention to the striking series of canyons in the volcanic 
rocks on the northern coast of Hawaii. There are bluffs 
with an elevation of a thousand feet, and enormous gorges 
that extend inland with almost perpendicular walls, some 
of which are said to be 2000 feet in height. The gorges 
are nearly or quite as deep near their upper ends as at 
the lower ends, and they have flat bottoms. They were 
formed as V-shaped gorges on the land, and have sunk 
until their lower ends were occupied by the sea, forming 
deep fjords which were soon filled by material derived partly 
from the sea and partly from streams. Other interesting 
features are dealt with by Mr. Branner. 
A FULL account of the life and work of the late Prof. 
Cornu is contained in the Revue générale des Sciences for 
October 30. The appreciation is from the pen of M. C. 
Raveau. 
Tue lecture on the periodic system of the elements de- 
livered by Sir William Ramsay at the recent meeting of the 
German Association at Cassel (see Nature, October 15, p. 
586) has been published in pamphlet form by the firm of 
J. A. Barth, Leipzig. 
AmonG articles dealing with scientific subjects contained 
in the November reviews and magazines, we notice two 
dealing with recent expériments on radium. One is by Mr. 
J. B. Burke on the radio-activity of matter, and is contained 
in the Monthly Review, the other, on the riddle of radium, 
is by Mr. A. S. M. Hutchinson, and is published in 
Pearson’s Magazine. ‘The latter magazine gives consider- 
able prominence to science this month, for in addition to the 
article mentioned, there is one on ‘‘ Our Descent from 
Monkeys,’” by Mr. S. S. Buckman, illustrated by photo- 
graphs showing habits and characteristics that link man to 
monkey forms, and also descriptive accounts of the 
Waimangu geyser, New Zealand, and the habits of wood- 
cocks.. 
A PAPER read by Mr. Edmund McClure at the Church 
Congress held at Bristol last month is a satisfactory indica- 
tion of the sympathetic attitude which the churches now 
show towards scientific research. Mr. McClure’s paper 
was entitled ‘‘ The Aids which Science gives to the 
Religious Mind,’’ and in it, after referring to Mendeléeff’s 
periodic law and the recent work of Sir W. Crookes and 
Sir W. Ramsay, he asks :—‘‘ Does not the religious mind, 
which lives and moves in the sphere of the unseen, find an 
aid in such an extension of the reach of the mental eye? ”’ 
It is encouraging to know that scientific work and thought 
can inspire reflections on the relation between the visible 
and invisible universes. 
Messrs. Townson and Mercer, of Camomile Street, 
London, have submitted to us for examination a form of 
extensimeter designed by the Rev. G. B. Lavelle, of Water- 
ford. The method of measuring linear expansion upon 
which the construction of the apparatus depends, is already 
well known in physical laboratories, and the apparatus is an 
elaborate form of one described in elementary books on 
NO. '776, VOL. 69] 
NATURE 
37 
practical physics. The instrument consists of a _ brass 
cylinder half a metre long, with side tubes for the ingress 
and egress of steam. The half-metre metal rod of which 
the linear expansion is to be determined rests on the bottom 
of the cylinder, and its other end passes through a hole ina 
movable metal cap to the cylinder. Temperatures are 
measured by thermometers introduced through india-rubber 
stoppers in the side tubes, and the spherometer is supported 
on a brass plate with a hole in the centre, the plate being 
so supported that it and the spherometer can be moved away 
from any issuing steam. A dry cell and electric bell are 
supplied with the apparatus to provide for greater accuracy 
in determining the instant of contact between the sphero- 
meter and the metal rod, but this seems an unnecessary 
elaboration. 
Hicu vacua for distillation under reduced pressure can 
be rapidly produced by filling the apparatus with carbon 
dioxide and condensing this with liquid air. Liquid carbon 
dioxide cannot be used, as it contains 0-75 per cent. by 
volume of dissolved air, but carbon dioxide snow gave good 
results; the dissolved air, like that dissolved in water, 
contains an excess of oxygen, the proportion being 24-1 per 
cent. by volume. The most convenient method is to pre- 
pare the gas from marble and hydrochloric acid, and to 
exhaust to 30 mm. by means of a water-pump; this oper- 
ation is repeated four times, and on cooling with liquid 
air a vacuum of 0-1 mm. is produced. The lowest pressure 
recorded was 0-026 mm. when rubber connections were used, 
but in a vessel made wholly of glass the vacuum required 
for the production of kathode rays could be obtained. Ernst 
Erdmann, in describing this method in a recent number of 
the Berichte, adds that in London liquid air costs less than 
fivepence per kilo. 
Tue additions to the Zoological Society’s Gardens during 
the past week include a Ring-tailed Lemur (Lemur catta) 
from Madagascar, presented by Lady Campbell; a Grey 
Seal (Halichoerus grypus) from the West Coast of Ireland, 
two Meyer’s Parrots (Poeocephalus meyeri) from South-east 
Africa, two Yellow-billed Cardinals (Paroaria capitata) 
from Chili, five Bungoma River Turtle (Emyda granosa), 
three Roofed Tortoises (Kachuga tectum), three Indian Eryx 
(Eryx johni), four Conical Eryx (Eryx conicus) from India, 
a Four-lined Snake (Coluber quatuorlineatus), South Euro- 
pean, deposited; a Polar Bear (Ursus maritimus) from Nova 
Zembla, purchased. 
OUR ASTRONOMICAL COLUMN. 
Revision oF RowLanp’s WAVE-LENGTHS.—In view of the 
extreme importance to workers in astrophysics of having a 
perfectly trustworthy system of standard wave-lengths, Prof. 
Hartmann reviews, in No. 3, vol. xviii., of the Astrophystcal 
Journal, the methods used by Rowland in constructing his 
wave-length tables, and points out their sources of error. 
He shows that Rowland made the metallic are wave-lengths 
given in his “‘ New Table of Standard Wave-lengths ”’ 
coincide with those of the solar spectrum by applying purely 
empirical corrections which cannot now be found. In a 
series of tables Prof. Hartmann also shows that differences, 
amounting in some cases to 0-03 unit, exist between the 
solar and metallic wave-lengths, and suggests that further 
experiments should be performed, on similar lines to those 
pursued by Michelson and Fabry and Perot, for the purpose 
of determining a general factor—the F of Fabry and Perot 
—by which the whole of Rowland’s table might be reduced 
to a rationalised standard from the equation A=(F and P)Fo, 
where (F and P) is the absolute wave-length found by the 
French observers, and Fo is the factor mentioned above. 
This would produce an errorless wave-length on Rowland’s 
scale for each of the thirty-three lines measured by Fabry 
