554 



factors in iletenmning this latter action is the i)rf'Son(*e or absence of 

 pliospliatos. A saccharine sohition free from phosphates ferments nunli 

 better without tlian witli fluorides; while in a sobition containin.mdios- 

 pliates the reverse is true. The apparent action «»f the i)hosphat«s and 

 fluorides was weaker in proportion as the amount of yeast in the wort 

 increased. 



Sodium as a plant nutrient, A. Atterberg {Ihut. landir. Presse, 

 ]Ss],p. ]()3')). — Altliou;;h it was hin^ a^io shown by means of water 

 cultures that j)lants can make a perfectly nornuil development without 

 sodium b(!in{i furnished, the fact remains that sodium is a very common 

 constituent of the ash of plants, and this led the author to test the 

 (picstion whctln'r this clement mijiht not be capable of replacing in part 

 other similar plant constituents, and esjjecially potash. Two series of 

 experiments were made the past year with black Tartarian oats, which 

 were <;rown in jxtts lilled with (piartz sand and watered with nutritive 

 solutions contaiiiinjf acid jtotassium phosphate, magnesium sulphat4\ 

 and potassium, sodium, and calcium nitrates. Difterent amounts of the 

 ]>(»tassium were rei)la<'ed by like amounts of sodium in the first series 

 and of calcium in the scioiid series. The second series received no 

 sodium salts. It was expected that with the diminislied sup]ily of 

 ]>otash salts the yield would fall off, but should the plants be able to 

 use the sodium in i)la<e of jiart of the potash the decrease in yield wouhl 

 not be as large as in the calcium series. All of the trials were made in 

 duplicate. The average yields were as follows: 



These results, the author believes, clearly show that sodium may fill 

 a very imiioitaiit fiiuctiou in case of a deliciency in ]»otassiiiin. and that 

 it is tlieicforenot to be regarded as an altogether useless plant constitu- 

 i'lit. These experiments he states show that the practice of a])plying 

 salt to the soil is a rational one from a scientific standpoint, and that the 

 large amount of sodium salts contained in many of the Stassfurt salts 

 is not to be regarded as useless ballast, but as possessing certain values 

 for the nutrition t>f plants. 



ThrtMigh ]»iivate t'orrcspondence he learns that Professor Wagner of 

 Darmstadt has obtained results similar to tlie above. 



