1922.] Indian Science Congress. L.S.C. 53 
amined by Geyslar tubes, and other special bg tubes about 25 
in length, furnished with snd side tubu ilur 8, sea sh freshly prepare 
pure and piste silver 8 icone to ust cover the plat 
electrodes sealed nto seo Pal bes, an = he ahaneevcd cells aed. the 
study of abso onption were glass tubes of different lengths forolaned “with 
glass or quartz w 
The exper mene pelos — 
(2) eee sso emission spectrum is a line spectrum depending on the 
e of discharge. As the intensity of discharge increased 
sate i nes are autos ced while others disappe 
(<i) The absorption n spectra const (1) of a banded spectrum in the 
yellowish-green region, and (2) of a principal absorption band 
e ultra violet, aa width of = band de panting on the 
pressur a thickne the lay 
(vit) The Cinnlpel absorption band shits towards the less refrang- 
ible side, with the increase of A c Weig 
(iv) Boos Law does not seem to hold "apad in the case of these 
vapours. 

A modified form of double slit spectrophotometer. —By 
. L. NaARAYANA. 
Being engaged in some spec ctrographic pork on the ope spectra 
of vapours and saiaons in the visible and ultra-violet Ming the need 
for a good spectrophotometer is felt. And a modified of double slit 
evi i 
ea 
photometer. It consists mainly of a n electromagnetically maintained 
pendulum (T=0°5”) wed bob of = poets — of two slits one above the 
other, whose widths can be adjusted by two micrometer scrow The 
slit widths are varied anitil scant eiaisation rf obtained. 
Movement in n-dimensions.—By R. VaIpyaNATHASWAMI. 
nt and from espeys saree of order 
From the geometry of move 
in real spaces, the definition is fcnol of congruent transforma tions in 
non-Euclidean space with the Absolute Quadric Ex? = 0, as C ollineators 
represented ogonal transformations, viz the reflect e 
nd 
ace a 
general quasi-regular Euclidean movement. 
Thunderstorms in Trivandrum.—By K. BR. RAMANATHAN. 
derstorm record Looe in the 
Some results cid = analysis of pee — cert seaprinprsece- sty rod 
Teiviedeass "Obseev ory are given 
bution of thunde ate ios is a a edd 
show that thunderstorm activity 15 greate: 
lout aa a 4 ees fH maximu m_opportanity for the formation of stron, 
pao, currents of hamid & 
On upper air correlations.—By P. C. guamags ge 
i th in which upper ait 
- racy nar acta he distribution of 
ents 
coed ar party si conditions on the surface of the qe ~_ 
correlation between the pressure pe 9 
