290 EXPERIMENT STATION EECORD. 



"(1) Prepare a 24-hour culture of Bacillus coli in plain broth of standard 

 composition and reaction; (2) add 10 cc. of this standard culture to 1 liter of 

 agar [1.5 per cent agar] and mix thoroughly; (3) pour the infected agar into 

 _ sterile tubes of convenient length [1 meter] and of exactly 1.5 cm. diameter 

 and allow to harden, after closing the ends with sterile rubber stoppers; (4) 

 allow to harden at 20° C. ; (5) prepare dilutions of the desired disinfectants 

 and a standard 5 per cent carbolic acid solution — the latter is the standard to 

 which the other disinfectants are referred; (6) place the disinfectants so pre- 

 pared in sterile beakers, allowing 50 cc. for each agar cylinder; (7) remove 

 stoppers from the infected agar tubes, and permit the contents to nm out slowly 

 as a long cylinder ; with a sterile knife cut off portions by transverse cuts of 

 2 cm. length, and allow these smaller cylinders to fall directly into the disin- 

 fectant solutions, 1 cylinder for each time interval selected; (8) note the 

 temperature of the solutions (they should be kept at exactly 20° C. during the 

 experiment) ; (9) note the time at which the cylinders were dropped into the 

 disinfectant solutions; (10) at the end of stated intervals (usually at hourly 

 intervals for preliminary tests) remove 1 cylinder from each solution with 

 one of the sterile holders mentioned above, wash it thoroughly with sterile 

 water, and remove a core from the center with a sterile piece of quill tubing 

 (3 mm. bore) ; (11) place these cores in lactose fermentation tubes, after they 

 are properly labeled, and incubate at 37° C. for several days, making daily 

 observations; (12) compare the killing times of the various solutions tested 

 with that obtained for carbolic acid, and determine the carbolic coefficient of 

 germicidal and penetrating powers combined." 



In tests with some common disinfectants and a 72-hour incubation, there 

 was no growth after 1 hour's exposure to 4 per cent formalin ; no growth 

 after 3 hours' exposure to 1 per cent formalin, or 1 per cent corrosive sublimate 

 solution ; and no growth after 5 hours' exposure to 5 per cent carbolic acid, 

 0.25 per cent formalin, and 10 per cent chlorid of lime. Even after 5 hours' 

 exposure, however, there was growth with 1 per cent carbolic acid, 0.1 per cent 

 corrosive sublimate, 4 per cent chlorid of lime, 2 per cent hyco, 1 per cent 

 cresol, and 2 per cent sulphonaphthol. 



KURAL ECONOMICS. 



Farmers of forty centuries, F. H. King (Madison, Wis., 1911, pp. IX+.'tJfl, 

 figs. 2JiS). — This book is a historical presentation and discussion of the agricul- 

 tural practices and customs of China, Korea, and Japan as seen by the author 

 in a personal study and survey of the 3 countries. It shows their methods of 

 intensive agriculture and utilization of waste ; the area, yield, and cost of the 

 leading crops ; modes of travel and transportation ; and the customs, manners, 

 etc., of the people. 



Agricultural competition between the West and East in the United States 

 of America, K. STEiNBRticK (Killin Arch., 1 (1911), No. 1, pp. lS3>-223, pi. 

 1). — In this article are presented notes and statistics as to agricultural compe- 

 tition between the Eastern and Western States in this country, giving general 

 agricultural statistics for the 2 sections ; the causes of the western movement ; 

 and data as to the comparative profitableness of farming in the East and West 

 and their future prospects. 



Massachusetts: Her agricultural resources, advantages, and opportuni- 

 ties, with a list of farms for sale, J. L. Ellsworth (Boston, 1911, 2. ed., pp. 

 169, pis. 9). — This pamphlet was prepared by the Massachusetts State Board of 

 Agriculture, and presents a list of farms for sale in Massachusetts, giving the 



