a 
January 8, 1914] 
NATURE 543 
which are necessary to consider in the design of a 
stable aéroplane, especially as regards the tail-plane. 
The cost of electric cooking was discussed by Prof. 
Morris, with reference to the result of one year’s 
working in a flat within the London area. A paper 
by Mr. A. E. Bawtree on bank-note engraving was 
illustrated by a number of photographs describing 
various methods in general use for the prevention of 
forgery. The author showed examples of a new 
system of a geometrical character, which cannot be 
imitated by repetition work, or by mechanical devices 
such as the pantagraph. The system which was not 
described was stated to allow the incorporation of a 
design which could only be made visible by a special 
screen. The concluding paper at this mecting was 
read by Mr. C. H. Lander on the frictional loss in 
steam pipes, and described experiments which agree 
with a dimensional formula due to Osborne Reynolds. 
A joint meeting of Sections A and G took place on 
the Monday morning to discuss the report of the 
committee, appointed last year, to consider certain 
of the more complex stress distributions in engineer- 
ing materials. The principal results of modern in- 
vestigations on combined stress were discussed by 
Mr. W. A. Scoble, while alternating stress was simi- 
larly dealt with by Messrs. Mason, Rogers, and Eden, 
and a special report on the resistance of tubes to col- 
lapse was contributed by Mr. G. Cook. The discussion 
upon the report was opened by Prof. Perry, the chair- 
man of the committee, who urged the importance of 
coming to a definite arreement as to the criterion of 
failure in a material subjected to stress. The dis- 
cussion on the various sections was continued by Mr. 
Stoney and other engineers, and covered a wide range 
of subjects connected with the experimental investiga- 
tion of stress distribution in engineering materials. 
A Section A paper by Prof. Coker was, for the 
convenience of the meeting, read immediately after 
the termination of the joint discussion; it described 
the construction of polariscopes for examining the 
stress distribution in large models of engineering 
structures built up of transparent materials. A second 
paper by the same author described the preliminary 
results of an investigation upon the stress distribution 
in rings subjected to internal or external pressure, 
with apparatus which leaves every part of the ring 
free for measurement except the surface exposed to 
fluid pressure. 
A paper contributed by Mr. T. Reid, described some 
experiments on the flow of solids based on the well- 
known experiments of Tresca. Lead cylinders divided 
in halves by a diametral plane are grooved to receive 
tin wires, which latter serve to map out the flow 
produced when pressure is applied to the cylinders. 
The experimental results appear to show that a very 
slow flow is stable, and that above a certain limit 
there is a condition resembling turbulence in a fluid. 
A paper by Mr. A. Robertson described experiments 
on the strength of free-ended struts, in which Euler’s 
formula is shown to hold good down to the length 
for which the stress given by this law is equal to the 
stress at yield, and, below this limit collapse occurs, 
when the load per square inch is equal to the yield 
stress. A concluding paper by Mr. A. T. Walmisley 
described the properties of non-ferrous metals which 
are of importance in structural engineering. 
On the Tuesday morning the first paper on an 
engineering theory of the gyroscope was read by Mr. 
J. W. Gordon, who pointed out that when a gyroscope 
is precessing freely it is absorbing power, while in 
forced precession it is transmitting. By the applica- 
tion of suitable constraining devices many important 
-practical instruments can be constructed, of small size, 
for the steering of ships, the prevention of rolling and 
pitching of aéroplanes, and the like. A short note by 
NO. 2306, VOL. 92] 
Prof. Wilson on tests of metals and alloys, directed 
especial attention to the increased brittleness and rise 
of electrical resistance of duralumin on prolonged ex- 
posure to the atmosphere. 
Papers dealing with various matters connected with 
wireless telegraphy were also read by Prof. Howe, 
who described the nature of the electromagnetic waves 
employed in radio-telegraphy, and the mode of their 
propagation. Dr. Eccles discussed atmospheric 
refraction and absorption as affecting transmission, 
and Prof. Marchant, the effect of atmospheric condi- 
tions on the strength of signals received at Liverpool 
from Paris and other wireless stations of great power. 
The final paper on Tuesday morning was read by Mr. 
W. R. Cooper, and described some practical sugges- 
tions for shortening the tests of temperature rise in 
electrical machines under working loads. 
As in previous years, a meeting on the Wednesday 
was necessary for the consideration of several impor- 
tant papers, and a programme on civil engineering 
subjects was followed with much interest by a large 
audience. Dr. Vaughan Cornish described the land- 
slides in the Culebra Cutting of the Panama Canal, 
especially those in which subsidence of the banks has 
caused numerous upheavals of the canal bottom. 
A paper on the reconstruction of the station at 
Snow Hill, Birmingham, was read by Messrs. 
Gleadow and Shackle, in which the structural steel] 
work was very fully described. The effect of harbour 
projections was discussed by Mr E. R. Matthews, 
and he advocated the use of piers inclined at such an 
angle to the shore that moving sand and shingle 
tends to sweep past the end of the pier and settle on 
the lee side. The transport and settlement of sand in 
water was also described, with many experimental 
illustrations, by Dr. J. S. Owens. An apparatus was 
also exhibited for exploring sand bars and river beds. 
It consisted of two concentric tubes closed above and 
open below, and provided with stop-cocks so that 
water under pressure can be forced through the inner 
tube to sink the apparatus in the sand or other mate- 
rial. When the desired level is reached a stop-cock 
communicating with the annular space is opened to 
allow a return passage for the water under pressure, 
and this carries with it a sample of the material at 
the base of the apparatus, and delivers it at the 
outlet. 
These interesting experiments concluded a_ very 
successful programme of the Engineering Section at 
the Birmingham Meeting. 
UNIVERSITY AND EDUCATIONAL 
INTELLIGENCE. 
Bristot.—The degree of D.Sc. in engineering will 
be conferred on Mr. Charles F. Smith, who has sub- 
mitted to the University records of his research worl: 
and publications in connection with electrical engineer- 
ing. . 
Lonpon.—The degree of doctor of science in chem- 
istry has been conferred upon Mr. F. G. Pope, an 
external student, of East London College. In addi- 
tion to a thesis entitled, ‘‘The Fluorine Group,” Mr. 
Pope submitted a list of printed contributions to the 
advancement of science, published independently or 
conjointly. : 
The degree of doctor of science in geology has been 
conferred upon Mr. E. H. Pascoe, external student, of 
University College. Mr. Pascoe presented a published 
thesis entitled, ‘‘The Oil Fields of Burma,” together 
with some further. contributions to the advancement of 
of science, published independently. 
The following lectures to advanced students of the 
University, and to others interested in the subjects 
