466 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



had always found something coming out, following the ball ; and 

 sometimes unburned powder. 



Mr. Babcock stated that the principle could not be applicable 

 to ordnance, for they are already far less than 32 diameters in 

 length. It is now the practice to make rifles shorter than form- 

 erly. They are made 27 inches long, instead of three feet or 

 more. 



Mr. Sykes suggested a form for a projectile, Avith spiral wings 

 to cause it to revolve, and with a chamber in the rear for a rocket 

 composition. 



Mr. Babcock stated that the explosion of the gun had been 

 found to destroy completely the rocket composition. 



Mr. Johnson. — Another objection would be that the velocity of 

 the ball itself would be a little greater than that of the issuing 

 stream. 



Subject for discussion. — The subjects selected for the next 

 meeting, were "Dredging" and " Soluble Glass." 



Adjourned. 



American Institute, Polytechnic Association, ) 



December 19, 1861. ] 

 Prof. Cyrus Mason in the chair. 



COTTON FLAX SILK. 



The Chairman proposed that the subject of " Textile Fibres " 

 should be taken up on the second Thursday in January, at which 

 time he would give the results of his microscopic examinations. 



Mr. Churchill stated that upon a microscopic examination of 

 twenty or thirty different specimens of flax prepared by a modi- 

 fication of Claussen's process he had found fibres of spiral struc- 

 ture, flat and twisted like cotton. 



Mr. Tillman stated that the flax fibre, as prepared by Chevalier 

 Claussen,. is like a glass tube, and utterly worthless for manufac- 

 ture. He had found another material however which showed the 

 cotton fibre. 



Mr. George H. Bowley exhibited a sample of tree silk from 

 Nicarauga. The silk is the product of a nest of worms which 

 cluster like snow upon the trees. It has not been reeled ; but 

 the natives make ropes of it, and it is very strong. The worms 

 seem to prefer one kind of tree, and those trees are completely 

 covered ; probably 50,000 of them being on one tree. 



