814 Proceedings of Societies. [December, 
outlets. The Stubden Reservoir had been a cause of anxiety, 
the original culvert of masonry proving leaky. It had been 
abandoned in favour of a tunnel lined with cast-iron plates 
backed with concrete, terminating in a cast-iron valve-tower, 
erected from the design and under the superintendence of Mr. 
A. R. Binnie, M. Inst. C.E. The embankment was cut down, 
the original culvert taken out, and the embankment was then 
made up solid in thin layers, the new tunnel being used to run 
water off during the reconstruction of the work. No leakage of 
any description had since been noticed, the valve-tower and tun- 
nel being water-tight. The Leeming Compensation Reservoir 
for mill-owners had been originally made with a circular culvert 
having a slip joint and iron shield where it crossed the puddle- 
trench. This culvert was seriously fractured by the subsidence 
of the bank, which was mostly on a clay foundation, and it was 
considered unsafe to fill the reservoir. On the suggestion of 
Mr. Rawlinson, C.B., M. Inst. C.E., and of Mr. Binnie, on the 
latter taking charge of the Bradford Corporation Water-Works, 
the old culvert was abandoned, and a new tunnel was substituted, 
similar to the one at Stubden. The original culvert was after- 
wards filled on the inside with concrete, and the reservoir was 
successfully filled with water, no leakage or disturbance having 
occurred up to the present time. In the case of the Leeshaw 
Reservoir, which was in course of construction, on Mr. Rawlin- 
son’s inspection it was resolved to abandon the culvert already 
cracked, and to substitute a tunnel outlet and valve-tower of 
cast-iron, similar to those at Leeming and Stubden : this had 
been successfully done, the reservoir filled, and the work had 
since proved most satisfactory. In two of the above cases the 
culverts were so damaged as to be a strong argument in favour 
of tunnel outlets distinct from the embankment. 
Physical Society. — The first meeting of this Society for the 
Session 1879-80 was held on Saturday, November 8th, Prof. W. 
G. Adams in the chair. 
The first paper read was “ On an Analogy between the Con- 
ductivity for Heat and the Induction Balance Effect of Copper-tin 
Alloys,” by W. Chandler Roberts, F.R.S. Mr. Roberts traced a 
remarkable resemblance between a curve representing the induc- 
tion balance effect of the copper-tin alloys published by him in 
June last, and the curve of Calvert and Johnston for the con- 
ductivity of heat, and, on the other hand, he showed that the 
induction curve does not agree with Matthiessen’s curve for the 
electric conductivity of the same alloys. In the course of his 
paper Mr. Roberts expressed a hope that Prof. Hughes’s beauti- 
ful instrument will enable us to determine whether the relation 
between conductivity for heat and electricity is really as exact as 
it has hitherto been supposed to be. 
