SEED - TESTERS. 13 



necessary in order both to thoroughly wet the cloth and to 

 kill any mold or other germs. When again cool, adjust the 

 cloths on the brass rods and put in the seeds. Each fold 

 will hold 25 large seeds, like beans, and a hundred or more 

 small seeds. Water is placed in the pan, but not enough to 

 touch the folds of cloth ; the four flaps drop down into it, 

 however, and keep the cloths sufficiently wet by capillarity, 

 which is increased by the long nap on the under surface of 

 the cloth. The folds are numbered consecutively, and the 

 record kept by the numbers. 



"The advantages in a pan of this kind are the facility 

 with which the seeds may be examined and counted, the 

 thorough and uniform moisture of the seeds throughout 

 the longest trials, its lightness and cleanliness. It is nec- 

 essary to renew the cloths from time to time, as they will 

 slowly rot out, even with tne best of care." 



a Az. 



ii. An absorbing block seed-tester. 



A device of a wholly different character, used in Ger- 

 many, is shown in Figs, u and 12 (Annals Hort., 1890, 268). 

 It consists of three parts : a tin tray (c) for holding water ; 

 a block of gypsum (b) which sits in the tray and contains 

 several compartments for the reception of the seeds, and 

 which is kept moist by capillary attraction ; a glass cover 

 (a). The apparatus is seen at work in Fig. 12. This 

 device works upon a principle which has long been util- 



