GYPSUM. 59 
plied to plot No. 3; if 90 per cent., it would get 25 ths. 
more plaster than plot No. 3. 
“The plots receiving plaster and superphosphate are 
the two best of the series. Plot No. 5. is a little the best, 
and probably received a little more real plaster than No. 3. 
One thing is clear: the soluble phosphate of lime in the 
superphosphate did no good, for on the plot No. 5 we 
have plaster alone; and on the other plot (No. 3) we have 
plaster and soluble phosphaie; and yet the crop is no 
better from the two together than from the plaster alone.” 
Other experiments made since, render it evident thatif the 
augmentation of the yield is less striking in some instances 
than in the above, the application of gypsum is uniformly in 
a very high degree beneficial. Its effect is most manifest 
upon soils not rich in vegetable matter, and especially upon 
clay lands. Such soils being well adapted to sugar produc- 
tion from this cane, its effects are very marked upon them. 
But it is the direct and peculiar influence which it exerts 
upon the growth of the plant that is especially noteworthy, 
and which, when more generally known, is likely to en- 
hance its value as a manure for the sorghum. ‘This con- 
sists in the fact that gypsum stimulates some organs of the 
plant to extraordinary development, while it has no such 
action upon others,—it increases greatly the size of the 
slems,—in a slight degree the quantity of the leaves, while 
it really diminishes the quantity of flowers and seeds. In 
the cane, this strong growth of stems is not, as when the 
plant is encouraged to a luxuriant expansion by animal 
manures, or a rich vegetable soil, attended by any diminu- 
tion of the saccharine quality of the juice, but rather an 
increased richness. Upon clover, it has long been known 
to exert a similar influence. It increases the weight of the 
stems at the expense of the leaves, flowers, and seeds. In 
plants, as in animals, special points of excellence may be 
