On the Strength of Cylindrical Steam Boilers. 



73 



13. I am not aware that this subject has been previously treated 

 in a general manner, at least as it regards several of the points above 

 presented. Mr. Oliver Evans made some particular calculations of 

 the strength requisite to sustain the pressure in a boiler of known di- 

 mensions, under a tension of 1500 lbs. to the square inch. In the 



Vol. XXIIL— No. 1. 10 



