1885.] NEW YORK ACADEMY OF SCIENCES. 13 



stone of the Capitol weighs 157 pounds, and has a hardness ap- 

 proaching that of granite. 



DISCUSSION. 



Dr. a. II. Elliott, being called upon for an opinion regard- 

 ing the durability of the imported " Carlisle " stone, said that he 

 could not express a confident opinion, as he had not made a 

 study of the stone, but he regarded it as inferior in durability to 

 varieties of native sandstone. 



Dr. a. a. Julien said there are two varieties of the 

 " Carlisle " stone; one kind from Corse Hill, and another from 

 Balloch Mile. Although it is a porous stone, and probably 

 not adapted to our climate, it had been much used by architects 

 because of its warm color, and the ease with which it could be 

 worked and carved. 



Dr. Elliott stated that experiments made by the Municipal 

 Gas Co., upon exposed buildings near the North Kiver, had sliown 

 that even one coating of boiled linseed oil was a useful preserva- 

 tive of building stone. 



The Chairman remarked that pulverized sandstone mixed with 

 linseed oil had been used for many years for roofs and for 

 covering walls. He gave examples of buildings so treated in 

 New York city and elsewhere. In most cases the stucco had 

 finally cracked, and had been removed. 



Dr. Elliott observed that one reason for the shorter life of 

 stone-work compared with brick- work is that less care is usually 

 taken with it. Brick surfaces are often painted and repointed. 

 If stone were often oiled, it would certainly, in increased dura- 

 bility, repay many times the cost. 



Dr. Julien said that oil had been considerably used in later 

 years. It lasts five or six years and then requires renewal. It 

 is only asuperficial protection. It should be applied to a building 

 as soon as erected. Usually the remedy has not been used until 

 decay and disintegration have reached beyond where the oil pene- 

 trates. In some cases it has been found that the back of stone 

 lying in walls of buildings is more decomposed than the face. 



Mr. George F. Kunz gave an account of the meteor, which 

 according to the newspapers, had fallen with terrible effect upon 



