250 BAXTER, WEATHERILL AND SCRIPTURE. 



resembles closely that used by Baxter, Moore and Boylston 16 for the 

 preparation of phosphorus tribromide, by Baxter and Moore 17 for the 

 preparation of phosphorus trichloride and by Baxter and Stark- 

 weather 18 for the preparation of tin tetrachloride. Two bulbs, A 

 and B, of about 300 cc. capacity serve as stills or receivers. The 

 separatory funnel D is employed during the introduction of the mate- 

 rial. The flask C of one liter or more capacity is an expansion reser- 

 voir for removing permanent gases. The small bulbs a, b, c, etc. are 

 fractionating bulbs. The various parts of the apparatus may be dis- 

 connected by sealing the capillaries F, G, J, K, etc. By means of the 

 special joint L, the final receiver B may subsequently be connected 

 with another similar system without exposure to air or moisture. 



The special joint L is shown on a large scale in Figure 1. The sealed- 

 in capillary P is closed at the end and is scratched with a file at several 

 points to facilitate breaking. To break the joint the closed tube of 

 glass weighted with mercury Q is allowed to strike the capillary with 

 some force. Bruner and Bekier, 19 Briscoe and Little 20 and Baxter 

 and Starkweather 18 used a similar device, while Richards and Craig 21 

 employed a magnetic hammer instead of one operated by gravity. 



First the stopcock E is made tight by rings of grease on the ends of 

 the cock and by pouring a small amount of mercury into the separatory 

 funnel D. The whole apparatus is next exhausted through // and the 

 capillary G is sealed. Next D is filled with silicon tetrachloride and 

 the mercury and nearly all the tetrachloride are admitted to A. 

 Again a small amount of mercury is poured into D to seal the stop- 

 cock and as soon as possible the capillary F is sealed. By sealing off 

 the globe C at ./ a large part of the permanent gases originally dis- 

 solved in the liquid chloride can be removed. The more volatile 

 fractions of material are condensed in some of the small bulbs, a, h, c, 

 by means of liquid air or carbon dioxide-alcohol mixture, and are sealed 

 off. Then the main portion of material is distilled into B which is 

 sealed off at K, leaving the least volatile fraction in A. Subsequently, 

 if desired, the residue in A can be distilled into d, c,f, for examination. 



16 Baxter, Moore and Boylston, These Proceedings, 47 590 (1912); Jour. 

 Amer. Chem. Soc, 34, 263 (1912); Z. anorg. Chem., 74, 365 (1912). 



17 Baxter and Moore, Orig. Com. Eighth Internal. Cong. Appl. Chem., 

 Vol. II, 21 (1912); Jour. Amer. Chem. Soc., 34, 1644 (1912); Z. anorg. Chem., 

 80, 189 (1913). 



18 Baxter and Starkweather, Jour. Amer. Chem. Soc, 42, 907 (1920). 



19 Bruner and Bekier, Z. f. Elektrochem, 18, 369 (1912). 



20 Briscoe and Little, Jour. Chem. Soc, 105, 1321 (1914). 



21 Richards and Craig, Jour. Amer. Chem. Soc, 41, 131 (1919) 



