re . 
OcToBER 9, I9I 3] 
te 
NATURE 
177 
fenry, physics master at the Reims Lycée, describes 
how he has applied a well known form of micromano- 
meter to make measurements in a number of direc- 
ions in which a manometer is not often utilised. The 
anometer consists of a U tube with wide limbs 
joined by a horizontal capillary tube. The limbs are 
about half-filled with carbon tetrachloride, and the 
‘capillary contains a small bubble of air Any slight 
difference of pressure at the ends of the capillary 
‘produces a considerable motion of the bubble. The 
instrument is calibrated by tilting the tube support by 
“means of a screw at one end. M. Henry shows how 
the instrument may be used to measure the excess of 
‘pressure in a soap-bubble and the effect of charging 
‘the bubble electrically, a small volume, a mass of a 
few grams, the density of a gas or of a solid, small 
amounts of heat, specific inductive capacity, difference 
of potential, a flow of gas, and the pressure exerted 
_ by a sound-wave. 
Tue determination of sulphur in illuminating gas is 
the subject of Technologic Paper No. 20 of the Bureau 
of Standards, by R. S. McBride and E. R. Weaver, 
issued by the Department of Commerce, Washington. 
Experiments were made with the gas referees’ ap- 
paratus and the apparatus designed by Elliot, Hinman- 
Jenkins, Drehschmidt and Somerville. The results 
of a series of comparisons are given, in which many 
variations were made to determine the best conditions 
of operation and the sources of error. The referees’ 
‘apparatus appears to be most used in America as well 
as here, and possesses the advantages of simplicity 
and convenience; the accuracy obtainable with this, 
as with other forms, has been often over-estimated. 
The concluding portion of the pamphlet deals with the 
estimation of the sulphate in the liquid condensate, 
__and details are given of the gravimetric determination, 
a rapid turbidimetric method, and a volumetric method 
based on that due to Holliger. Although most gas 
companies in this country are now free from any 
restriction as to the amount of sulphur present in 
their gas other than sulphuretted hydrogen, the 
pamphlet will be very useful to any chemists having 
to deal with this problem. 
In the Bulletin de la Société d’Encouragment (No. 
6, p. 805) Prof. Camille Matignon discusses in an 
interesting paper some of the less known recent pro- 
cesses for the industrial fixation of atmospheric 
nitrogen. The well known methods utilising an 
electric flame are only briefly touched upon, but 
especial reference is made to Schloesing’s process of 
absorbing the nitrous gas so obtained with lime at a 
temperature of 300°. The principal processes dealt 
with are those of Haber, in which nitrogen and 
hydrogen are made to combine directly under the 
influence of a catalytic agent, and that of Serpek 
based on the formation of aluminium nitride by 
heating a mixture of alumina and carbon in a current 
of pure nitrogen at a temperature of 1800°. The latter 
method has a particularly bright industrial outlook 
owing to the fact that by decomposing the nitride 
with dilute alkali not only is ammonia obtained, but 
NO. 2293, VOL. 92| 
“In the Journal de Physique for August, M. A. : 
it is possible by means of it to transform bauxite into - 
alumina suitable for the aluminium industry at a 
much reduced cost. The action between the alumina 
and carbon is effected in revolving cylinders, which 
are lined with aluminium nitride itself, as being the 
only sufficiently refractory material which will with- 
stand the high temperatures employed. 
Rep Book No. 182 of the British Fire Prevention 
Committee contains an account of tests on three 
window openings filled in with Luxfer  electro- 
glazing. The record gives the effect of a fire of 
ninety minutes’ duration, the temperature reaching 
1500° F. and not exceeding 1650° F., followed by the 
application of water for two minutes on the fire side. 
This test again indicates that forms of special glazing 
are being produced commercially that can serve most 
efficiently to stop the spread of a fire of considerable 
severity. It is the second occasion upon which 
“lights”? presented for test by the British Luxfer 
Prism Syndicate, Ltd., have met the strain of a ninety 
minutes’ test at temperatures exceeding 1500° F. 
Red Book No. 183 contains records of tests on two 
steel-cased reinforced concrete doors by Messrs. Chubb 
and Sons, one hung on runners and made to slide, 
the other hung on hinges, fixed in a reveal. The 
latter door secured ‘full protection” (Class B). The 
partially successful efforts to produce a single door 
able to do the work of two iron doors required under 
the London Building Act are of considerable technical 
importance. The radiation through the doors was 
very small. Doubtless the problem of making a 
sliding door flame-proof around the edges will be 
overcome. 
OUR ASTRONOMICAL COLUMN. 
A New Comer.—A Reuter message from Perth, 
W.A., dated October 7, reports that a faint new 
comet has been observed in the position R.A. 
gheeagimss Decri3” 4s N- 
Tue RetuRN OF WESTPHAL’s Comet.—The identifica- 
tion of Mr. Delaran’s comet with Westphal’s comet of 
1852 is now complete, its positions being in accord 
with those predicted on the assumption of the object 
being the return of the comet of Westphal. 
The following ephemeris for the current week is 
given by Prof. H. Kobold in a Supplement to the 
Astronomische Nachrichten, No. 4684 :— 
12h. M.T. Berlin. 
; R.A. Dec. Mag. 
. m Ss. 3 
OGIO rue se 2h 10/24 ; "Bet Si20) ..cmenee 
oh ESv02 Clara 2) 
Il II 25 9 571 
12 Oz 10° 450" a.) eecay 
13 B4AA,  -c.m PLA te 
14 ASS) ane kana 
Th sce Be sos Ros 
Thm er2zt (024... 13/548) \enemo 
After observations on September 28, the corrections to 
the above ephemeris are as follows:—R.A. —34s., 
Dec. +9/9’. 
As this comet does not reach perihelion until 
November 26, and as it is slowly approaching the 
earth, its brightness will be increased. In appearance 
the nucleus is described as well defined but elongated, 
and surrounded by a nebulosity 20’ in diameter. The 
tail has been observed to be 12° in length, while a 
