594 IOWA ACADEMY OF SCIENCE 



iii water, or still better, in brine (or giving the last washing in 

 brine), and then rolling it well in dry powdered, water-slacked, 

 fresh lime, some hours before sowing." 



An article published in the Cultivator, 1837, Vol. 11, page 

 107, mentions a method which no doubt was in vogue at that 

 time. The grain was soaked in a brine solution for twelve hours 

 after which it was rolled in fresh slacked lime before sowing. 



After 1856 the records indicate that copper sulphate was 

 used to some degree with varying success. In 1887 and 1888 

 Jensen (29) published the results of his experiments with hot 

 water — a method which still bears his name. Following the in- 

 troduction of the Jensen method, Kellerman and Swingle (33) in 

 1889, published a rather complete treatise of the history and 

 methods of control. As a result of their experiments potassium 

 sulphide proved an efficient preventive. The treatment con- 

 sisted in soaking the oats in a % per cent solution of potassium 

 sulphide (l 1 /^ lbs. of salt in 25 gallons of water) for a period 

 of 24 hours. From this time on there is a noticeable interest in 

 the oat smut problem. As a result sundry methods of control 

 have been tried in an effort to secure one that would be conven- 

 ient, efficient, and cheap. Of the many materials experimented 

 with for the control of the smut disease the following have come 

 to the attention of the writer. Kellerman and Swingle (33) have 

 tried various combinations of copper sulphate, copper nitrate, 

 potassium sulphate, mercuric chloride, potassium bichromate, 

 sodium hyposulphate, sodium hydrogen carbonate, corrosive 

 sublimate, chloroform vapors, carbon bisulphide, ether vapor, 

 ammonium hydrate vapors, verdigris, sulphur, salicylicid acid, 

 castile soap, hot water. L. H. Pammel (17) experimented with 

 ammonieal carbonate, ferrous sulphate, bordeaux mixture. By 

 others, ceres pulver or powder, soap, tar dips and various other 

 products have been tried. 



Since it is the purpose of the writer to follow the history and 

 the use of formalin for the control of the oat smut, other treat- 

 ments will not receive consideration in this paper only as they 

 have a bearing on the subject at hand. 



Early History of Formalin. 



Goff (25") in his treatise on the use of formalin mentions that 

 formalin was first discovered by a German scientist who had 

 produced the gas from wood alcohol. Its germicidal properties 



