33 Of the Use of Steam 



and decisive, of which I intend at some future period 

 to give to the public a full and detailed account, that 

 the strength of paper is such, when several sheets of it 

 are firmly attached together with glue, that a solid cylin- 

 der of this substance, the transverse section of which 

 should amount to only one superficial inch, would sus- 

 tain a weight of 30,000 pounds avoirdupois, or above 

 13 tons, suspended to it, without being pulled asunder 

 or broken. 



The strength of hemp is still much greater, when it is 

 pulled equally in the direction of the length of its fibres. 

 I found, from the results of my experiments with this sub- 

 stance, that a cylinder of the size above mentioned, com- 

 posed of the straight fibres of hemp glued together, would 

 sustain 92,000 pounds without being pulled asunder. 



A cylinder of equal dimensions, composed of the 

 strongest iron I could ever meet with, would not sus- 

 tain more than 66,000 pounds weight; and the iron 

 must be very good not to be pulled asunder with a 

 weight equal to 55,000 pounds avoirdupois. 



I shall not, in this place, enlarge on the many advan- 

 tages that may be derived from a knowledge of these 

 curious facts. I have mentioned them now, in order 

 that they may be known to the public ; and that ingen- 

 ious men, who have leisure for these researches, may be 

 induced to turn their attention to a subject, not only 

 very interesting on many accounts, but which promises 

 to lead to most important improvements in mechanics. 



I cannot return from this digression without just 

 mentioning one or two results of my experimental 

 investigations relative to the force of cohesion, or 

 strength of bodies, which certainly are well calculated 

 to excite the curiosity of men of science. 



