Se 
SCIENCE AND INDUSTRY. 
methods of testing materials, and several new machines have been 
designed for this purpose. Dr. Stanton’s “Alternating stress” machine 
is one of these. In it the test piece is subjected alternately to com- 
pression and extension, and: the failure of materials due to “fatigue” 
can be investigated thereby. Three impact-testing machines—the 
largest of which is sufficiently powerful to break a full-sized railway 
* coupling at one blow—belong to the equipment. Recently, experi- 
ments on the relative values of different lubricating oils have been 
carried out, using a special machine, in which the efficiency of a worm 
gear, when lubricated with the oils under test, is measured under 
different conditions of load. 
The Aeronautics division, though attached to the Engineering De- 
partment, is separately subsidized by the Government, and is used _as 
the official laboratory of the Advisory Committee on aeronautics. New 
premises have recently been built and equipped. The method most 
generally adopted for the investigation of aerodynamic problems is to 
test scale models of aircraft (or parts thereof) in wind-channels. In 
these the model is ‘supported on a special weighing machine (by which 
the forces and moments acting on it can be measured), and a stream 
ROAD TESTING MACHINE. 
of air blown past it through the channel. The smallest of the channels 
is 4 feet square. There are two or three 7-ft. channels, and a new 
channel 7 feet by 14 feet in section has just been completed. Many of | 
_the staff are very expert mathematicians, and have ample scope for the 
employment of their special knowledge in direction. 
The Metallurgy Department is under the superintendence of Dr. W. 
Rosenhain, a native of Melbourne, and a graduate of its University. 
His interests lie chiefly in the study of the Physics of Metals, which 
term may be used to include Metallography and the whole subject of 
the thermal and mechanical treatment of metals and alloys. From a 
study of the crystalline structure of metals, most extensive and valuable 
information has been obtained. For example, the microscope has often 
revealed causes of failure in metal parts, when the testing machine, by 
itself, has given but little indication of the trouble. Among the equip- 
ment of this part of the Metallurgy Department are special metallo- 
graphic microscopes, and special electric furnaces for investigating the 
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