'784 Transactions of the American Institutb. 



other words, the distillated substance contahis 9^ per cent of abso- 

 lute alcohol. 



The several parts of this convenient alcohol indicator are inclosed 

 in a substantial box, about 9^" long, 6|" wide, and 4|" high. It 

 merely takes half a minute to put the apparatus together or to 

 take it asunder. 



The alcoholic substance of any spirituous fluid is therewith just 

 as precisely and quickly determined, as by the " Vaporimeter," and 

 without beiu": obliged — as it is the case with the latter — to use 

 fresh-burnt lime. 



PAPER HATS. 



Dr. Rowell exhibited specimens of ladies' hats, made of paper. 

 The mold is made by coating the ordinary straw hat with plumbago, 

 and then electrotyping it. This is made solid by backing up with 

 lead. The straw is then burned out, which leaves a perfect mold. 

 The paper is pressed in this mold by an hydraulic pump, and 

 becomes so hard that it always retains its shajje, and will stand the 

 heat of boiling water for five minutes without injury. It is more 

 durable than the felt hat, and about half the price of the straw 

 hat. Paper and powdered rosin are all that is used in the hat. 



Dr. D. D. Parmelee remarked that it was impossible to exactly imi- 

 tate this grain of wool. Search this wide world over, and no two 

 pieces of wood with the grain exactly alike, could be found. This 

 fact was about being used, with the aid of the electrotype process, 

 to produce an engraving for the backs of our "greenbacks," that 

 would be almost impossible to counterfeit. 



Mr. Solomon Mcllroy stated that paper was being used for an 

 immense variety of purposes. He had an engine that was packed 

 with paper, which stood very well. Paper felting and paper belt- 

 ing are now much used. 



PUMPS. 

 In the discussion on this subject. Dr. Vanderweyde said that 

 water wa^ kept out of the low land of Holland, by pumps worked 

 by windmills. The pumps were somewhat like the paddle wheels 

 on the stern of some of our Western steamboats. A man was in 

 constant attendance to regulate the surface of the wind sails. This 

 plan was in use for a long time, but now steam is used. With this 

 centrifugal pump, there is a steady current of water obtained, and 

 none of the thumping incident to most other pumps is observed. 

 This pump works with most advantage when the water is kept 



