MAGNESIUM AND BERYLLIUM. 



61 



In 1890 Sestini ff undertook to determine whether wheat could be 

 raised in culture solutions in which magnesium sulphate was replaced 

 by beryllium sulphate. He sowed the grains in quartz sand which 

 had been treated with hydrochloric acid to remove all mineral impuri- 

 ties, and watered the plants with a culture solution containing 

 beryllium sulphate in place of magnesium sulphate. The plants 

 reached a height of 90 to 95 cm., but the control experiment showed 

 the superiority of magnesium over beryllium, as will be seen by 

 the following comparison: 



Wheat grown — 



In the beryllium solution . . 

 In the magnesium solution 



Number of 

 seeds. 



283 

 322 



Weight of 

 seeds. 



drums. 

 12.31 

 15. 20 



Weight of 

 singles 1. 



Grams. 



0. 135 

 .■172 



The harvested seeds were grown again in the same way/' Of twenty 

 seeds of the plants grown in beryllium solution, however, only seven 

 germinated, and only three of the plants produced seeds, the resulting 

 crop of fourteen seeds weighing only 0.37 gram and averaging only 

 0.026 gram. This clearly shows that beryllium can not replace mag- 

 nesium in wheat, and very probably also not in any other of the 

 phanerogams. The fact that the first generation yielded a much better 

 result than the second must be ascribed to the presence of a relatively 

 large amount of magnesium phosphate in the seeds used. 



In an experiment made by the writer with shoots of Tradescantia 

 placed in culture solutions containing 0.1 per cent beryllium sulphate 

 in one case and 0.1 per cent magnesium sulphate in the other, the 

 lower leaves of the beryllium plant commenced to die after several 

 weeks, and the newly developed upper leaves scarcely reached one- 

 third the normal size, these shoots dying oil' after eight weeks, while 

 in the control case they were still in a healthy condition.'' 



In regard to algae, the writer has observed that a solution of beryl- 

 lium sulphate in which the other mineral nutrients are wanting exer- 

 cises an injurious influence sooner than does the magnesium sulphate. 

 Some threads of Spi rog yra communis were placed in 0.2 per cent of 

 these salts dissolved in purest distilled water, and it was found after 

 two days that the number of dead and injured cells was much larger 

 in the former case than in the latter.' 7 



In a subsequent experiment the amount of both these sulphates was 



« Le Staz. Agr. Ital., Vol. XX; Centralbl. f. Agr. Cheni., 1890, p. 464, and 1891, p. 558. 

 & The ash of the beryllium plants contained 2 per cent of BeO. 

 ^Mineral nutrients are stored up in the nodes, as already mentioned. 

 ^For further information relative to the noxious effect of magnesium salts in 

 absence of calcium see pp. 49-51. 



