2646 Journal of Applied Microscopy 



simple clamps on flanges. Beginning at top of O, the wall K extends upward, 

 cone shaped, to an apex J, through which passes the lower end of the block-tin 

 worm A, This joint will be more secure if the tin tube extends about one inch 

 below the apex and is braced as shown in Fig. 1. Immediately above the point 

 J the tin tube bends at almost a right angle and runs in a spiral direction cue- 

 ward and upward to the bottom of the condenser B, the bottom of which should 

 be about one and one-half inches above the point J. The spiral tube is shown 

 in Figs. 2 and 3. In the middle third of tube F, Fig. 3, is soldered a short piece 

 of tin tubing, in which a stop-cock I is placed, in such a manner as to form a 

 small trap in the bottom of tube F, which must be filled before the alcohol, 

 returning from the condenser, can flow back to the boiler. Fig. 3. This trap is 

 made by removing the bottom and spreading the sides of tube F to receive tube 

 H. Tube H, in Fig. 3, contains a stop-cock, which, when closed, causes the 

 return alcohol from the condenser to fill the trap and flow into the boiler and 

 when open permits the return alcohol to flow through tube H to the absolute 

 alcohol receiver. The lower end of tube H is to receive a three-eighths rubber 

 tube, which in turn connects with a glass tube the lower end of which penetrates 

 a cork in the absolute alcohol receiver, which is an ordinary large bottle. 



The worm should be of one-half inch block-tin tubing, the coils of which 

 should be from one and one-half to two inches apart and three-fourths of an inch 

 from the walls of condenser B. When the coil reaches the top of condenser B, 

 it should be deflected until the wall of the condenser is reached, here securely 

 fastened and then extend perpendicularly upward four or five inches. Condenser 

 B should be at least five inches in diameter and ten inches high, and firmly 

 attached to top K by four supports, E, E', E". It is necessary to have condenser 

 and top K one rigid piece to prevent straining the block-tin tube and disarrang- 

 ing the trap in tube F. Near the bottom of the condenser is a cold water intake 

 O, for three-eighths rubber tubing, with stop-cock. On opposite side one inch 

 from top of condenser is an outflow pipe, C, for a one-half inch rubber tube. 

 One-fourth of an inch from condenser, tubes C and D are deflected at 45° to 

 prevent tubing from kinking. Across the top of condenser run two bars at right 

 angles for supporting a handle to which is attached a rope which runs over a 

 small pulley fixed in a bracket a few inches above the condenser. By means of 

 this rope and pulley the condenser is raised so that the wall O of top clears 

 wall N of boiler and is then pushed to one side, so the boiler may be removed 

 from the bath for cleaning and refilling. If the condenser is thus handled there 

 is no danger of injuring the joint between O and N. The rubber tubing con- 

 necting the intake D with the water main and tube C with tube X must be suffi- 

 ciently long to permit the condenser to swing free of the boiler. 



The cheapest method of abstracting water from alcohol is by using fresh 

 well burnt lime, quick lime, according to the formula Ca 0-t-H2 O =^Ca (OH) 2, 

 which when expressed in atomic weight values is 55. S5 : 17.95 or 3.11 grams of 

 quick lime for each gram of water. Ordinary commercial 95 per cent, alcohol 

 varies from 92 to 95 per cent alcohol, so contains from 5 to 8 grams of water 

 per 100 cc. For safety it is best to calculate 5 grams of lime for each gram of 

 water and allow for 10 c. c. of water per 100 c. c. of alcohol. On this basis it 



