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that the upholders of it clung so tenaciously to their ideas. The more 
modern ideas on combustion were then treated through the medium of numer- 
ous experiments, and a wide definition of the term combustion was ultimately 
arrived at. The fact that the combustible body and the supporter of com- 
bustion were both essential and played equal parts in the process was shown 
by causing a jet of air to burn in an atmosphere of coal gas. Temperature 
of ignition, spontaneous combustion, and heat of combustion were treated 
experimentally, and reference was made to the manufacturer’s aim of obtain- 
ing maximum heating effect at minimum cost. In this connection the lecturer 
made mention of the recent developments which have taken place in the 
investigation of the phenomena of surface combustion, and exhibited the 
combustion of coal gas without flame, the mixture of coal gas and air being 
allowed to impinge on hot platinum foil. He indicated that similar results 
could be obtained with cheaper materials, and gave figures to show that by 
such methods steam could be raised in a large boiler in shorter time than 
by ordinary methods ‘of combustion. He also briefly indicated reasons 
accounting for the greater ‘efficiency of this type of combustion. 
Mr. T. Lewis Bailey, Ph.D., F.I.C., lectured on ‘“‘ The Development of 
the Heavy Chemical Trade.’’ The growth of the methods of manufacture of 
carbonate of soda was shortly reviewed, this entailing a comparison of the 
Leblane process and the Ammonia Soda process. A consideration of the past 
methods of production of chlorine (for the manufacture of bleaching powder 
and other materiais), and of the recent developments in technical electrolytic 
processes followed, which pointed to the replacement of existing chlorine 
processes by electrolysation of brine, whereby chlorine and caustic soda are 
produced, the result of developments in this direction being of necessity a 
gradual disappearance of the old Leblanc alkali process. Recent develop- 
ments in the manufacture of nitric acid and ammonia by synthetic methods 
were explained, together with the manufacture of nitric acid by oxidation 
of ammonia, and it was insisted that such methods of manufacture must be 
pushed on in this country, if we are to maintain our posititon and keep pace 
with requirements in the shape of nitrogenous fertilisers, for which there is 
an ever-growing demand. During the course of the lecture it Was, Moreover, 
made apparent that the various branches of chemical manufacture must hang 
together more in the future than they have done in the past, and that so- 
called waste products must receive continually increased attention, with a 
view to their economical utilisation. 
PHOTOGRAPHIC SECTION. 
The members of this Section have shown a keen appreciation of the 
country rambles, lectures and practical demonstrations which were specially 
organised on their behalf. Special demonstrations were given by Mr. A. E. 
Goodman, Mr. D. Brellisford Jones, the Hon. Secretary (Mr. F. W. Higgins), 
and others; and they were well attended by both the senior and junior mem- 
hers of the section. There was a special display of the summer work at 
the Annual Conversazione, which proved both an attractive and instructive 
exhibit. 
Mr. W. G. Schréder, A.R.C.A., gave a lecture on “Suggestions as to 
Pictorial Composition.” He described by the aid of diagrams and pictures 
the salient points to be aimed at in making good phototgraphic pictures, as 
well as those to be avoided. He also offered some friendly criticisms on a 
series of lantern pictures which were provided by the members. 
LITERATURE SECTION. 
On November 13th, Miss Clay lectured for the Literature Section on 
“Some Novelists: Meditations without Method.” The authors chosen for 
consideration were Ann Radeliffe, Fanny Burney, Jane Austen, Charlotte 
Bronté, and George Eliot. It was pointed out that though ‘‘ The Mysteries 
