146 APPLICATIONS OF CENTEIFUGAL FORCE. 



bent of a piece cut out of a sheet of zinc, soldered, and a roui 

 handle of iron wire inserted in two opposite holes punched in 

 collar ; the ends of the handle are bent into hooks. The stem 

 carefully heated until hot enough to melt sealing-wax, covered whil 

 hot with a layer of wax, the collar is then heated and pushed uj 

 the stem. After cooling, the sealing-wax which has oozed out 

 round is removed with a knife. 



The centrifugal drying machine is another applicatio 

 of this force; it is in use in laundries, dyeing work 

 etc., and consists of a large hollow cylinder, the bottom 

 and sides of which are perforated by a number of holes. 

 The linen to be dried is put into this, and the cylinder 

 is then made to rotate rapidly; in this way the line 

 is closely pressed against the sides, the water is given 

 off and thrown away through the holes of the cylinder. 



If the hand is brought near from the side to the 

 rotating plate of the whirling- table, we feel that the 

 air is rapidly thrown in all directions ; the particles 

 of air nearest to the plate are carried by the latter 

 round in a circle, until they fly off at a tangent. In 

 order to set the air into rotatory motion, a disc of 

 pasteboard, 16 cm in diameter, upon which eight perpen- 

 dicular radiating strips (indicated by dotted lines in 

 fig. 103) a re fixed, is screwed to the plate of the 

 whirling-table. This arrangement is surrounded by a 

 cylindrical cover made of pasteboard, just wide and 

 high enough not to touch the radiating strips at the 

 sides and above, when they are rotating. There are 

 two apertures at the bottom of this cap, which permit 

 the cord of the apparatus to pass. In the middle of 

 the top is a circular hole 4 cm in diameter, and laterally, 

 in the direction of a tangent to the cylinder, there is 

 fixed to it a square tube r r. When the plate is set in 



