200 



C. U. C. p. ALUMNI JOURNAL 



B OOK EXCHANGE COLUMN . 



Wanted. 



Pharmaceutical Era — 



V. 19 (1898), No. I (Jan. 6th). 

 V. 38 (1907), No. 19 (Nov. 7th). 



Pharmaceutische Ceiitralhalle — 

 V. 5 (1864), No. 7. 

 V. 7 (1866). 



V. II (1870), Nos. 2-23, 28, 36-39. 42, 



44-45- 

 V. 12 (1871). Nos. 6, 8. 24, 35. 



V. Z7 (1896). Nos. I, 8, 18, 22, 26, 

 27> Z^' 39' 43» 49- 



V. 53 (1912), Nos. 1-4, 7-1 1. 13, 16- 

 18, 20-22, 24, 26, 28, 32, 35, 36, 

 44-46. 52 and index. 



V. 54 (i9i3),Nos. 5-6,9-12, 16,49-51. 



Duplicates for Exchange. 



Pharmaceutical Journal (Lond.) — 



Ser. 3, V. 4 (1873-74)— V. 10 (1879- 

 80) [7 bd. vols.]. 



Ser. 3, V. 21 (1890-91) — V. 23 (1892- 

 93) [7 bd. vols.]. 



Ser. 4, V. I (July-Dec, 1895)— v. 9 

 (July-Dec, 1899) [9 bd. vols.]. 



Ser. 4, V. 13 (July-Dec, 1901); v. 15 

 (July-Dec, 1902) — v. 21 (July- 

 Dec, 1905) [8 bd. vols.]. 



Ser. 4, V. 23 (July-Dec. 1906) ; v. 26 

 (Jan. -June, 1908) — v. 28 (Jan.- 

 June, 1909) [4 bd. vols.]. 



Other lists of duplicates for exchange 

 will be given in succeeding numbers of 

 the Journal. 



AN UNUSUAL EXPLOSION IN 

 CONNECTION WITH POTAS- 

 SIUM CHLORATE.* 



By Floyd E. Rowland. 



There was nothing unusual about the 

 explosion itself, but the manner in which 

 it occurred is well worth mentioning and 

 bringing to the attention of all who have 

 occasion to use pestles which have 

 wooden handles. 



Everyone knows that disaster is sure 

 to follow when potassium chlorate and 

 sulphur are ground together ; but to have 

 a perfectly clean mortar and pestle sud- 

 denly explode with great violence, when 

 one is grinding an inert substance like 

 pumice stone, makes one pause and 

 wonder why. 



A pestle and an 8-inch mortar were 

 thoroughly cleaned and about fifteen 

 pounds of potassium chlorate were 

 ground with no disastrous results. The 

 mortar and pestle were washed and 

 dried. A few days later some crushed 

 pumice . stone was required in the lab- 

 oratory and the same mortar and pestle 

 were used. A loud explosion resulted. 

 The mortar and pestle were broken into 

 many pieces and thrown violently about 

 the room. One piece passed through a 

 window scarcely shattering the glass. 

 The room was filled with sulphur diox- 

 ide and fine particles of sulphur were 

 scattered over the floor and table. 



An examination of the pieces of the 

 mortar showed no traces of sulphur, but 

 quite large quantities of sulphur were 

 found adhering to the fragments of the 

 pestle. The wooden handle of this pestle 

 had been sealed into the ball part with 



'J 



our. Ind. and Eng. Chem. 



