176 farmers' and mechanics^ journal. 



The preceding, and the problem of the cardsj I consider as case^i 

 precisely similar ; the same effect produced by the same causes. 

 I, therefore, in a concise form, gave a similar explanation, which 

 was published in the United States Gazette some weeks since. 



1 have since seen a solution of the latter problem by Prof. Hare, 

 who attributes the etfect to a different cause. He supposes that 

 the blast coming out in various currents from the common centre 

 of the tube and disks, causes an afflux of the surrounding air to- 

 wards them, and as Mr. Perkins expresses it, (who explained the 

 problem of the valve in the same wa.y that Dr. Hare has that of the 

 cards,) "impinges" on the whole outer surface of the disk, and 

 counteracts the power of the blast, which acts only on a small part 

 of the inner surface. To satisfy myself of the fallacy of this, I used 

 means which I thought effectual to cut off all afflux of air towards 

 the disk, which could have a tendency to keep them together, when 

 I found the effect as prompt as before ; which made me conclude, 

 they were not kept together by any flow of air, but by the constant 

 and steady pressure of the atmosphere which rested on them at the 

 time the blast commenced, and continues unabated, while that on 

 the inner surfaces is lessened by being met and opposed by the 

 force of the blast, running out between the two inner surfaces of 

 the cards. 



1 attempted to illustrate this by a tube six inches in length, and 

 about the diameter of a large quill, at the end of which I fixed two 

 strips of paper 3-4ths of an inch wide, and extending about three 

 inches from the end of the tube ; on blowing with force through 

 the tube, the strips of paper were brought together by a very prompt 

 and rapid movement. 1 observed the same effect, when this tube, 

 with the strips of paper, was placed within another lube of 1 1-2 

 inch diameter and 10 or 12 inches long. l^I'Vanklin Journal. 



Specification of the Patent granted to Charles Bagenall FleeT- 

 wooD, of Parliament-street, Dublin, Gent, for a Liquid, and Com- 

 position, for making Leather, and other articles, Water-proof, — 

 Dated February 28, 1824. 



My new invented liquid and composition for making leather, and 

 ather articles, water-proof, consists of a certain compound of resin- 

 ous, oleaginous, and elastic matters, the proportions of which, and 

 the mode of mixing, I am about to describe. My process is as fol- 

 lows : I dissolve 10 lbs. of caoutchouc, or Indian Rubber, in 20 

 gallons of pure spirits of turpentine, by putting them both into a 

 tin vessel capable of holding at least 35 gallons ; 40 perhaps would 

 be as well ; — the caoutchouc should be cut into pieces, or slices, 

 of about 1-1 6th part of an ounce weight, to hasten the solution. I 

 then immerse the ves'-el into a boiler, previously filled with cold 

 water, and app'y the nre so as to produce the boiling of the water, 

 occasionally supplying the waste, caused by evaporation. In this 

 situation it remains until a perfect solution of the caoutchouc, in 

 the spirits of turpentine, is effected ; I then dissolve 150 lbs. weight 



