RECENT SCIENTIFIC NOTES. 617 
was found in this respect. It was also observed that the percentage of 
phosphorie acid inereased as that of potash diminished; so that in the 
abundant harvests it is proportionally less than in the scanty ones, vary- 
ing from 10 to nearly 18 per cent. The proportion of sulphuric 
acid is tolerably constant, varying from 5 to 6 per cent. The per- 
centage of chlorine ‘vé aried very much; namely, from 2 to nearly 8 
per cent. The quantitative difference in the percentage of chlorine in 
the ashes was found throughout to have a direct relationship to the 
amount of the crop itself. Should this inference, which the author now 
presents as provisional only, be substantiated by the further experi- 
ments he proposes to make, it may be considered that the combinations 
of chlorine have the same significance in the cultivation of the potato, 
‘that gypsum has to various other cultivated plants. 
Constituents of the milk of different animals—From a late examination 
of different kinds of milk, with reference to their solid constituents, it 
has been ascertained that asses’ milk is most diluted, containing 
searcely 9 per cent. of solid matter. Next comes human milk, with 
somewhat over 11 per cent., while mares’ milk contains ‘L7 per cent. 
The average is seen in the milk of the goat and of the cow. In refer- 
ence to the percentage of caseine and albumen, human milk is poorest, 
containing only 4 per cent. of caseine; cows’ milk nearly 5 per cent., 
with more than 4 per cent. of albumen. Again, goats’ milk, with 
nearly 6 per cent. of caseine and albumen, as far as known, has a larger 
amount of albumen than that of any other mammal. The smallest 
quantity of butter is found in asses’ milk; that of the goat contains 
the largest, or nearly 7 per cent. Sheep, milk is most nutritious, as it 
contains 11} per cent. of proteine matters and hydrocarbons ; and while 
the milk of the cow contains only about 4 per cent. of milk sugar, that 
of the mare has § per cent., which renders it very prone to alcoholic 
fermentation, and has given rise to its employment by the Tartars in the 
production of an intoxicating liquor, known as quass. 
FERTILIZERS. 
Sulphate of magnesia as a manure.—The accumulation of sulphate of 
magnesia, or epsom salts, as a waste product at a mineral-water estab- 
lishment in Konigsberg, where it is offered for sale at about 15 cents 
per hundred-weight, has suggested its use for agricultural purposes, as 
its constituents enter largely into the composition of most vegetable 
substances. Magnesia especially is found in considerable quantity in 
the seeds of various cultivated plants, and especially in corn, &c. The 
experiment has already been tried of applying the sulphate of magnesia 
to one part of the field, and the sulphate of lime, or gypsum, to the other; 
and, according to Protessor Goltz, it is stated that, in the case of clover 
especially, the difference in favor of the magnesia was very marked, 
although the general nature of its agency appears to be quite similar to 
that of the gypsum. Both seem particularly valuable in this connec- 
tion, on account of entering directly into the composition of the plant 
instead of requiring a ecrtain transformation before being taken up. 
The sulphate of magnesia, as stated by Professor Goltz, has perhaps a 
still more important application in the stable, acting like gypsum in 
retarding the decomposition of the manure, and fixing the ammonia de- 
veloped trom it. The sulphate of magnesia, however, acts more quickly 
and energetically than gypsum, in consequence of being very soluble in 
water; just the contrary being the case with gypsum. Jrom the pre- 
