TRAXSACTIOXS OF SECTION G. 759 



mens prepared from the beams tested transversely. The following inferences were 

 drawn : — 



(a) The tensile strength does not seem to be much affected by kiln-drying, but 

 in the majority of cases it is diminished. 



(b) Kiln-drying invariably and greatly increases the compressive strength. 



(c) Kiln-di-ying invariably and greatly diminishes the shearing strength, and 

 therefore increases the tendency of beams to fail by longitudinal shear. 



(d) The transverse strength is increased by kiln-drying, in consequence of the 

 increased strength given to the portion of the timber in compression. 



(e) Kiln-drying increases the co-efficient of elasticity, and with kiln-dried 

 specimens the changes of deflection and length are practically directly proportional 

 to the changes of load, whether the specimen is being loaded or relieved of load. 



(f ) The last (viz. e) is also true of specimens in a normal state, i.e. specimens in 

 which the moisture is in equilibrium with the moisture present in the atmosphere. 



(g) Timber ia extremely sensitive to variations in the hygrometric condition of 

 the atmosphere. 



(h) The development of shakes and the tendency to longitudinal shear are 

 much less in specimens which have been air-dried than in those which have been 

 kiln-dried. 



4. A Neic Apparatus for Studying the Rate of Condensation of Steam on a 

 Metal Surface at Different Temperatures and Pressures. By H. L. 

 Callendar, M.A., F.R.S., Professor of Physics, and J. T. Nicolson, 

 B.Sc, Professor of Jlechanical Engineering, of McGill University, 

 Montreal. 



[Ordered by the General Committee to be printed in extcnm. See Keports, 



p. 418]. 



As the result of some experiments by electrical methods on the measurement 

 of the temperature changes of the walls and steam in the cylinder of a working 

 steam-engine, which were made at the McDonald Engineering Building of IMcGill 

 University in the summer of 1895, the authors arrived at the conclusion that the 

 well-known phenomena of cylinder condensation could be explained, and the 

 amount of condensation in many cases predicted, from a knowledge of the indicator 

 card, on the hypothesis that the rate of condensation of steam, though very great, 

 was not infinite, but finite and measurable. An account of these experiments was 

 communicated to the Institute of Civil Engineers in September 1896, and will, it 

 is hoped, be published in the course of the ensuing year. In the meantime the 

 authors have endeavoured to measure the rate of condensation of steam under dif- 

 ferent conditions by a new and entirely different method, with a view to verify the 

 results of their previous work, and also to estimate the probable effect of wetness 

 or superheating of the steam, and the infliuence, if any, of the film of water adhering 

 to the walls of the cylinder. 



5. Tests on the Triple-expansion Engine at Massachusetts Institute oj 

 Technology. By Cecil H. Peabody, Professor of Marine Engineer- 

 ing and Naval Architecture. 



The experimental engine is a horizontal three-crank triple-expansion engine, 

 built by the E. P. Atlis Company of Milwaukee. The diameter of the high- 

 pressure cylinder is 9 inches, that of the intermediate cylinder is 16, and that 

 of the low-pressure cylinder is 24 inches. All these pistons have a stroke of 

 30 inches. Th« high-pressure and intermediate cylinders have Corliss valves of 

 the ordinary type, moved by eccentrics with a small angular advance. The 

 valves for the low-pressure cylinder are moved by two eccentrics, each working 

 its own wrist plate ; one of the eccentrics has a small angular advance, and 



