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FOREIGN AND MISCELLANEOUS INTELLIGENCE. 



I. MECHANICAL SCIENCE. 



1. STIFFNESS AND STRENGTH OF TIMBER. 



IN a series of experiments undertaken by Lieutenant T. S. Brown, 

 to ascertain the relative stiffness and strength of different kinds of 

 pine used in building, it was found that the ratios of the stiffness of 

 white pine, spruce, and southern pine, were as the numbers 1, 1-111 

 and 1 -807. When the weights producing the flexure were increased, 

 it was found that the failures of the wood began at the top. The 

 upper fibres, for rather less than half the depth of the beam, were 

 gradually crushed and broken off in the bending of the specimen ; 

 and at last, when no more weight could be supported, a fracture sud- 

 denly took place, the lower fibres being drawn asunder *. 



2. PROPORTION BETWEEN THE METRE AND ENGLISH YARD. 

 M. Francceur, in an elaborate memoir on the proportion between 

 French and English measure, has found that the metre is equal to 

 39.37079 English inches, and the English imperial yard equal to 

 O m .9 14383 48 numbers which may be relied on with the utmost 

 confidence f. 



3. ON THE VELOCITY OF AN ELASTIC FLUID WHICH FLOWS FROM 

 A RESERVOIR INTO A GASOMETER. 



In most books of natural philosophy we find the following proposi- 

 tion stated as if it had been founded on data as certain as the pres- 

 sure of the atmosphere. l The flowing of an elastic fluid into a 

 vacuum takes place with the velocity due to the height of a column 

 of fluid of the same density with that contained in the vessel, and 

 whose weight would produce the pressure to which the fluid is sub- 

 mitted.' M. Navier has shewn that this could only be true on the 

 supposition, that the density of the fluid in the tube or orifice through 

 which it flows was the same as that in the reservoir, which, from the 

 diminished pressure, is obviously not the case. The results to which 

 he has arrived will for ever banish this false proposition from books 

 of natural philosophy J. 



4. ON THE DISCHARGE OF A JET OF WATER UNDER WATER. 

 (R. W. Fox, Esq.) 



Having observed that a communication of mine * On the Discharge 

 of a jet of water under water,' inserted in No. 47, of the Philoso- 

 phical Magazine, has been noticed in the last number of the Journal 

 of the Royal Institution, I will take this opportunity of mentioning, 



* Silliman's Journal, vol. xix. p. 292. 



t Mem. de 1'Acad. des Sciences, tome x. p. 50. J Ibid, 



2 R 2 



