ABSTRACT OF PROCEEDINGS. XX1x, 
rapid corrosion or rusting away of the iron casing at one 
of the Australian artesian bores, where abundance of car- 
bonic acid gas was evolved at the rather high temperature 
of 100° Fahr., the water also contained alkaline carbonates 
and bicarbonates with sodium chlorides, silica, etc., amount- 
ing to between thirty and forty grains of total solid matter 
to the gallon. This is an admittedly difficult case to deal 
with, and probably a specially hard and resistant alloy will 
be required to stand the prolonged and severe action of the 
water in question. The protection of ironwork under usual 
conditions is best effected by the use of a paint or an enamel 
having a co-efficient of expansion equal or nearly equal to 
that of the iron itself, so that cracking or bursting of the 
skin of paint shall be prevented which would otherwise lead 
to exposure of thebare iron to outside influences. Dr. Angus- 
Smith’s composition, the Bower-Barff process, red lead, iron 
oxide, asphaite, and graphitic paints were each considered, 
the author holding a high opinion of simple pure red lead 
and genuine linseed oil as an excellent covering for most 
purposes. Galvanised iron, lead, bronze, Muntz metal, and 
copper were each referred to, especially to the action of 
the air of towns and manufacturing districts. 
The following papers were taken as read :— 
3. ‘On the elastic radial deformations in the rims and 
arms of flywheels, and their measurement by an optical 
method,’ by A. BOYD, B.sc., B.E., Stud. Inst.c E. |Communi- 
cated by Prof. WARREN, M. Inst. C.E., Wh. Sc. | 
The author points out that hitherto the only experimental 
work that has been done on this subject has been to burst 
flywheels and measure their bursting speed, attempts being 
made to deduce the cause of weakness in any wheel from 
its mode offracture. Asthe wheels were almost absolutely 
shattered in each case, the first point of fracture was 
difficult to determine. In this paper, actual measurements 
