MECHANICS AND USEFUL ARTS. 73 



the cylinders, and forces the dirt and dust through other openings in 

 the concaves. The shanks of the teeth are shouldered even with the 

 face of the cylinder, and after they are driven home, a metallic plate 

 having notches of the same size as the teeth above their shoulders, is 

 screwed firmly upon them, thus rendering it wholly impossible for 

 them to escape until all the screws in the plate give way. 



An improvement in the cotton-gin, devised by L. Campbell, of 

 Columbus, Miss., consist in the employment of a concave, constructed 

 with a series of passages, in which the ginning saws work ; the sides 

 of said passages being covered with bristles or other elastic subtances, 

 for the purpose of more effectually freeing the cotton from impurities 

 as it is drawn through the passages by the saws. This concave is 

 also provided with a series of brushes which, in combination with the 

 brush fan of ordinary gins, spread the cotton evenly upon its dis- 



charge. 



WEAVING OF BROCATELLES. 



The weaving of this elegant sort of tapestry goods by power- 

 looms has been introduced at Humphreysville, Conn. The Journal 

 and Courier (New Haven) thus speaks of the enterprize : 



" The adaptation of heavy machinery to the production of silk 

 goods, is a stride in manufactures which only those can appreciate 

 who are familiar with the business. During three years of patient toil, 

 in the face of difficulties which seemed insurmountable, and sur- 

 rounded by discouragements which would have broken the spirit of 

 ordinary men, the projectors of this enterprize have moved steadily 

 forward with an unfailing confidence in their ultimate success ; and 

 we are rejoiced to learn their labors are being crowned with a rich 

 reward, exceeding their most sanguine expectations. The fabric they 

 manufacture has been brought to great perfection, and a large demand, 

 greater than their present facilities can supply, is pressing upon them 

 from the larger marts of trade. Bigelow's celebrated power-loom, the 

 use of which is confined to this company, has been adapted to this 

 work by the ingenuity of Mr. J. P. Humaston, to whom alone the 

 credit is due for the introduction of this new branch of manufacture ; 

 and so nicely is the machinery balanced, that the breaking of a single 

 thread, though scarcely larger than a twisted spider's web, throws the 

 whole machinery out of gear, and all the wheels, shuttles and pullies 

 are brought to a dead stand, that the thread may be mended. Indeed, so 

 ingenious is the adaptation, it seems almost to possess human intelli- 

 gence. This company are using only original designs, and so compli- 

 cated are some of these, it requires eight thousand cards, each per- 

 forated with from twenty to seventy holes, every one of which is 

 worked through the harness of the loom to represent a few inches of 

 the fabric correctly. Mr. Humaston has invented a card cutter, with 

 which a child can perform as much labor in a week, as two men can 

 in a month without it ; and this enables them to be prodigal in new 

 designs. For a hundred years these goods have been made in Europe, 



