proceedings of the rolytechnic association, 4^9 



American Institute, Polytechnic Association, ? 

 June 21, 1860. ] 



Professor Mason in the chair. 



granulated cork. 



S. W. Smith produced a specimen of granulated cork, called 

 in commerce, cork wood. He stated that among its other quali- 

 ties it was a non-conductor of heat, and was now used for lining 

 the under part of roofing for the purpose of keeping the upper 

 rooms cool. It has also the effect of deadening sound, and is a 

 non-absorbent of heat. It is used in packing fruit, &c. ; also, 

 in refrigerators. Fifty pounds of ice placed in a refrigerator 

 lined with cork has been known to remain entire, without melting, 

 for the space of ten days, while, in one without cork it would 

 melt in a few hours. It is manufactured by being simply ground 

 in a mill, and can be supplied at the rate of fifty cents per barrel. 

 The weight of a barrel full of this cork is eighteen pounds. Cork 

 wood, as it is called in commerce, is the outside bark of the cork 

 tree. 



Chairman. — How does the cost of this compare with charcoal ? 



Mr, Smith. — Charcoal would be cheaper. 



Chairman. — What is the relative value of this cork compared 

 with charcoal, as a non-conductor ? 



Mr. Smith. — I think charcoal is rather better than the cork. 

 My experience with charcoal in the manufacture of refrigerators 

 is, that the charcoal retains the moisture. It is not a costly job 

 to pack refrigerators with this cork. A barrel will not compress 

 half a bushel. 



The Chairman. — The weight of charcoal used in packing a 

 railroad car is about 2000 pounds, which is a fatal objection to 

 its use, this cork would prove an excellent substitute, on account 

 of its lightness. 



artificial leather. 



Mr. Pennyman produced a sample of what is called artificial 

 leather, made from the parings of harness, &c., and stated that 

 it was manufactured in the manner that paper usually is. This 

 is furnished at eight cents per pound, and can be made entirely 

 water-proof. It is manufactured at Anherst, Massachusetts. 



Mr. Fisher. — Can you put this into any form you please ? 



Mr. Pennyman. — It is only made at present in large slabs the 

 same as bristol board, but I believe that there could be machinery 

 made to put it into any form you please. 



