SECTIONAL TRANSACTIONS.— G. 393 



There are, however, many problems to be overcome before flight in the 

 stratosphere becomes commonplace, and such attempts as the altitude 

 record flight are of considerable value in determining how far the inherent 

 difficulties may be overcome. These problems include the provision of 

 a power unit which will retain sufficient power to enable the aeroplane to 

 reach the desired altitude, the special design of an aeroplane of adequate 

 wing surface and suitable aspect ratio, and supplying the occupants with 

 a sufficiency of oxygen. 



The paper deals with the altitude record flight of 53,937 ft. by Flight- 

 Lieutenant M. J. Adam on June 30, 1937, in a Bristol aeroplane powered 

 with a Bristol engine and flown from the aerodrome at the Royal Aircraft 

 Establishment, Farnborough, and outlines the factors governing the choice 

 of type of power plant, the design of the aeroplane and airscrew, and the 

 provision of a pressure suit for the pilot. A brief r^sum^ of the pilot's 

 report on the actual flight is also included . 



Prof. H. W. Swift and Dr. H. L. Haslegrave. — Experiments on sleeve 

 bearing lubrication (12.0). 



This paper deals with experimental work on a sleeve bearing 4 inches 

 diameter by 12 inches axial width under loads up to 10,000 lb. and at speeds 

 up to 1,200 r.p.m. 



The apparatus is described in detail, its calibration and behaviour are 

 discussed, and results are given of tests made with an entry angle of 90°. 



The bearing was loaded upwards by means of a letter-balance, lever and 

 dead weight system. Friction was measured separately on the bearing and 

 on the journal. Shaft displacements were determined from micrometer 

 measurements at both ends of the bearing. Oil pressures were measured 

 at thirty-two representative points on the bearing surface by means of 

 Bourdon gauges. 



The results obtained are in general conformity with theoretical expecta- 

 tions though certain systematic discrepancies are evident which are attributed 

 to a tendency to vibration at light loads and to the difficulty of measuring 

 the oil temperature in the film. 



Afternoon. 



Visits to L.M. & 8. Railway Research Station, Derby ; Bar-lock 

 Factory ; North Wilford Power Station ; Stanton Ironworks. 



Tuesday, September 7. 



Prof. E. W. Marchant.^ — Electrical vibrations and their applications in 

 television (lo.o). 



A description is given of the methods used for producing electrical vibra- 

 tions of various kinds. The dynatron oscillator is illustrated by a water 

 model with a valve having a controlling force which diminishes as the valve 

 opens. Such an arrangement, with a U tube connected across it, illustrates 

 the principle of action of this oscillator, the oscillation being demonstrated by 

 the movement of the water in the U tube. The principle of the thyratron 

 controlled ' time base ' for a cathode ray oscillograph or television receiver 

 is also illustrated by a water model. The capacity of the condenser in the 

 circuit giving the time base is represented by a small pivoted vessel so 

 arranged that when it fills it tilts over and empties itself. The flow of 



