418 SECTIONAL TRANSACTIONS.—B. 
cases of the rupture of the benzene and indol rings in tyrosine and tryptophane 
respectively. Mechanisms of oxidation at the temperature and reaction of the 
animal body; activisation of oxygen; the probable importance in physiological 
oxidations of the activisation and transport of hydrogen; Wieland’s views; 
the factors involved in the mobilisation of hydrogen atoms. 
6, Prof. E..C. C. Baty, F.R:S:,; Prof. TI. M. Hemsron, and W.'F. 
BarkER.—The Synthesis of Formaldehyde and Carbohydrates 
from Carbon Dioxide and Water. 
7. Prof. F. M. Jascer.—The Decomposition of Simple Organic Acids 
by Ultra-Violet Radiation. 
The author describes experiments on the action of the ultra-violet rays from 
a mercury arc on aqueous solutions of simple organic acids and their salts. It 
is shown that the course of the reaction tor each substance under given con- 
ditions of radiation is highly dependent on the presence or absence of special 
ions, which appear to act as directing catalysts. 
8. Prof. G. Barcrer, F.R.S.—Demonstration of Micro-Analysis of 
Compounds containing Carbon, Hydrogen, and Nitrogen. 
9, Reports of Research Committees. See pp. 243-250. 
Tuesday, September 13. 
10. Prof. F. M. Janarr.—The Measurement of Surface Tension over 
a wide range of Temperature. 
A method is described and illustrated which allows of the accurate deter- 
mination of surface tensions between — 80° and + 1625°. <A slow current of 
nitrogen enters the liquid through a platinum capillary immersed to a known 
depth, so that small gas bubbles are formed at the sharp edge of the tube, and 
the minimum gas pressure needed to cause the gas bubbles to burst is measured. 
This pressure is connected in a known way with the radius of the tube, the 
density of the liquid at the temperature given, and the surface tension sought. 
The method has been applied to many organic substances and inorganic salts, 
and the results are reviewed. 
11. Mr. Cosmo Jouns.—The Surface of Liquid Steel. 
12, Prof. C. H. Descu.—Surface Tension in the Solidification of 
Metals. 
The forms of the grains in solidified metals are examined and compared with 
those of foam cells. A close correspondence is found, indicating that the form 
of the grain boundaries is determined by surface tension. 
13. Dr. J. 8S. OwEens.—Suspended Impurities in City Air. 
This paper describes experiments carried out for the Advisory Committee 
on Atmospheric Pollution. The quantity of suspended matter in London air 
has been determined by means of automatic apparatus at South Kensington, 
Kew Observatory, and Westminster for several months, and curves are given. 
A new and simpie method of dust measurement is described. A measured 
volume is drawn through a small cell, in which the dust is deposited on a cover 
glass, which can be removed, mounted for examination, and preserved for 
reference. 
14, Mr. W. Tuomson.—Determinations of the Smoke Impurities in 
the Air of Manchester. 
Afternoon visits were arranged to the Chemical Laboratories of 
the University, Liberton, and of the Heriot-Watt College; to Messrs. 
Wm. Younger & Co., Abbey Brewery; Messrs. Duncan, Flockhart & 
Co., Manufacturing Chemists; The North British Rubber Co., Castle 
Mills; and The Broxburn Oil Co. 
