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Experiments on the Expansion and Contraction of Building 

 Stones, hy variations of Temperature, By William H. 

 C. Bartlett, Lieutenant United States Engineers * 



SiK, Fort-Adams, Newpoi-t Harbour, March 12. 1832. 



JLn the progress of this work, we have had occasion to use con- 

 siderable quantities of coping-stones taken from different locali- 

 ties, with all of which it has been found impossible to obtain 

 tight joints. The walls on which these stones were placed have 

 not undergone the slightest change ; and notwithstanding they 

 were laid with the greatest possible care, and their joints were 

 filled wiih the best cements that could be devised, yet, at the 

 Expiration of a few weeks, these joints were broken up by fissures 

 which extended from the top to the bottom of the coping. 

 These fissures were supposed to have arisen from a change of 

 dimensions in the coping-stones, in consequence of the ordinary 

 variations of atmospheric temperature ; and, with the view to 

 ascertain if the total amount of cracking could be attributed to 

 this cause alone, a series of experiments was instituted by order 

 of Colonel Totten, and continued from 18th August 1830 to 2d 

 June 1831. The circumstances connected with these experi- 

 ments, as well as their results, you will find subjoined. Colonel 

 Totten requests me to communicate them to you, supposing 

 that you may find them of sufficient practical importance to de- 

 serve a place in your Journal. 



These experiments were made nearly at the same time, upon 

 granite, limestone, and sandstone, the kinds of stone used for 

 the coping ; and for this purpose a piece of each was selected, 

 in such a manner that the three pieces were of nearly equal 

 lengths. The granite has a fine grain, is of a compact texture, 

 and was taken from a boulder at the head of Buzzard's Bay : 

 the limestone is white, has a fine grained crystalline structure, 

 and accompanies primitive rocks; it was taken from the quarries 

 of the Sing-sing State Prison, New York : the sandstone is from 

 the quarries in Chatham, Connecticut, and belongs to the old red 

 sandstone formation, according to the Rev. Edward Hitchcock ;-{: 



• Silliman's Journal, Vol. xxii. No. 1. April 1832. 

 t He now refers all the sandstone of the Connecticut valley to the new 

 red sandstone. 



