MECHANICS AND USEFUL ARTS. 65 



der being covered with silk in a gummy state, the book with the gold leaf is 

 opened and laid on the palm of the hand ; the machine something like a 

 turning lathe is moved; the edge of the leaf is made to touch the gum 

 silk, and it is quickly drawn round the cylinder covering the silk. This is 

 repeated until the entire surface of the roller is covered with gold leaf. A 

 piece of cloth or washed leather is fastened on a slip of wood, something like 

 a razor-strop. The roller is turned round and the strop pressed firmly upon 

 the leaf, which not only presses the leaf closer to the silk, but separates the 

 leaf between each of -the windings of the finest thread. Thus one side of the 

 finest thread is gilded. It is thus apparent that if gold and green, or any 

 other color, is desired in combination with gold, we have only, first, to dye 

 the thread the color we require, and then, by gilding one side, we secure the 

 combination wished. To gild the entire thread we have only to wind the 

 half-gilded thread on to another roller. The gilded side of the silk thread 

 necessarily winds next to the brass on the second roller, leaving the ungilt 



ti 



part of the thread exposed, and ready to be treated in the same manner as 

 before described, and so the process is completed. It is then wound on to 

 reels of the usual size, and permitted to dry thoroughly. The color by this 

 process is very beautiful, being the natural color of the gold leaf. The great 

 advantage of this over every other thread is its lightness and perfect flexi- 

 bility, for it can be wound and woven wherever any other thread can be 

 wound or woven. 



As regards cost it is, size for size, considerably dearer than the ordinary 

 gold thread, but as it measures a much greater length for the weight, it vir- 

 tually becomes, for wearing purposes, very much cheaper. 



MACHINE SPINNING. 



Machine spinning has now increased to such gigantic dimensions that it 

 forms one, if not the most important department of industrial labor. It is 

 calculated that there are at present in use throughout the world forty millions 

 of spindles used for spinning cotton, eight millions for spinning wool, and 

 three millions for spinning linen, severally divided among the various coun- 

 tries, as follows: Great Britain, 21,000,000 cotton, 2,470,000 wool, 

 2,000,000 linen; United States, 6,000,000 cotton, 1,400,000 wool, 15,000 

 linen ; France, 5,500,000 cotton, 850,000 wool, 350,000 linen ; Germany and 

 Switzerland, 3,500,000 cotton, 1,640,000 wool, 162,000 linen; Russia, 

 1,000,000 cotton, 510,000 wool, 50,000 linen; Belgium, 900,000 cotton, 

 200,000 wool, 150,000 linen; Spain, 800,000 cotton, 18,000 wool, 6,000 

 linen; Italy, Portugal and the rest of the world, 1,300,000 cotton, 912,000 

 wool, 264,000 linen. The acknowledged superiority of the spinning machine- 

 ry generally used in this country, enables us to produce a greater amount 

 of material per spindle than any other, which not only tends to lessen the 

 apparently great disproportion of the number of spindles employed here and 

 in Great Britain, but enables us to compete successfully with them in their 

 home market in the cheaper description of cotton goods. Improvements of 

 great value have been made of late years in the construction and operation 

 of spindles for cotton. One of the most recent is a short spindle to which is 



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