1o- Gish rery -, 
iene ‘ 
SECTIONAL TRANSACTIONS.—4A, B. 375 
o Scorpii may thus be considered as a Cepheid in a triple system, a case 
unique at present, which from the fact that it shows remarkable perturbations 
may bid fair to throw important light on the problem of Cepheid variation. 
50. Mr. R. Mevprum Stewart and Mr. J. P. Henperson.—Wireless 
Time Signals. 
The time signals emitted by Annapolis and Lafayette have been regularly 
observed at Ottawa for some years. A summary of the comparisons of time 
thus obtained between Ottawa, Washington, and Paris is given. 
Lhe comparisons have usually been made by the method of coincidences by 
extinction, in which the incoming wireless signals are gradually encroached 
upon and finally obliterated by the opening of a relay operated by a differentially 
rated chronometer. 
Comparisons have been made between observations by the above method 
and those by actual chronographic registration; the latter were also studied 
independently. It appears that in the case of chronographic registration the 
greatest precautions must be taken to avoid the introduction of variable relay 
lags, especially differences in lag between the incoming signals and the artificially 
introduced clock signals. Apart from photographic methods, and possibly 
those involving the use of a syphon recorder, the only satisfactory method 
appears to be the use of a relay of speed comparable with that of the audio 
valve oscillations, coupled with another relay in such a way as to ensure the 
carrying through to the chronograph of even a single pulsation of the primary 
relay. Even under such conditions the accuracy of chronographic recording 
appears to be no higher than that of the coincidence method, and the latter 
has the advantage that observations can be made of fainter signals. 
SECTION B.—CHEMISTRY. 
(For references to the publication elsewhere of communications entered in the 
following list of transactions, see page 465.) 
Thursday, August 7. 
1, Presidential Address by Sir Ropert Rospertson, F.R.S., on 
Chemistry and the State. (Page 53.) 
2. Prof. W. A. Bong, F.R.S.—The Activation of Nitrogen in the Explosion 
of Carbon Monowide-Air Mixtures at High Initial Pressures. 
The paper describes the principal experimental results obtained by the 
author in conjunction with Messrs. D. M. Newitt and D. T. A. Townend during 
the recent researches upon gaseous combustion at high pressures, in which it has 
been discovered that nitrogen exerts a peculiar energy-absorbing influence when 
carbon monoxide-air mixtures are exploded in a bomb at high initial pressures, 
which is not manifest at all when corresponding hydrogen-air mixtures are 
similarly exploded. The observed facts are explained on the supposition that 
there is some constitutional correspondence between CO and N, molecules (where 
densities are identical) whereby the vibrational energy (radiation) emitted when 
the one burns is of such a quality as can be readily absorbed by the other, the 
two thus acting in resonance. The nitrogen thus becomes chemically ‘ activatea’ 
in carbon monoxide-air explosions: at high initial pressures, and in such state 
is able to combine with oxygen more readily than does nitrogen which has merely 
been raised to a correspondingly high temperature in a hydrogen-air explosion. 
The influence of varying initial explosion pressures up to 100 atmospheres upon 
the said ‘nitrogen-activation’’ is shown, and the bearing of the results upon 
the problem of ‘ nitrogen-fixation’ discussed. 
3. Prof. James Kenpauut and Mr. Beverty L. Cuarce.—A New 
Method for the Separation of Elements of the Rare Earths. 
The ionic migration method ‘previously proposed for the separation of 
isotopes [Proc. Nat. Acad. Sci. 9, 75 (1923)} has been successfully extended 
