igof \ Garden, Field, and Forest of the Nation. 57 
surpassed all the land in the neighborhood in its barrenness 
for ordinary cultivated crops; in the year this land hardly 
grew so much fodder as would have sufficed for a single 
sheep. It consisted partly of sand, partly of coarse quartz 
and pebbles, with strata of sand and some loam. 
“Some of the soil was first tested by sowing it with seeds 
in pots after enrichment with some single mineral manure, 
with the result that not one of the plants got beyond flower- 
ering; this showed that the soil was bad enough for his 
purpose of testing the value of minerals as manure. 
“A number of mineral manures were then prepared for him 
according to prescriptions based on his analyses, and these 
were spread over the land; next he sowed on different sub- 
divisions of it wheat, rye, barley, clover, potatoes, turnips, 
maize. In some cases he added sawdust to the manure, and 
in one case he used stable manure; otherwise no ammoniacal 
! manure and no mineral matter was employed, except that to 
one plot he applied some forest soil and to another a mixture 
of forest soil and mineral manure. Even in the first year he 
had a harvest; the best results were given by those plots in 
which mineral manures were mixed with forest soil or stable 
manure. This, as he says, enabled him to correct his earlier 
j ideas of the functions of humus, which by its decay renders 
an extra supply of carbonic acid gas to the plants that is 
especially valuable at the early stages. Gradually, without 
any other supply of manure except mineral manure, the land 
so improved in productiveness that in the fourth year his 
crops excited the wonder of all who had known- the original 
state of it. 
“In 1849 this little farm was purchased by his gardener, 
who was then able to farm it with profit, raising some cattle 
on it yearly and getting such satisfactory crops of corn that 
in 1853 a neighboring farmer wrote: ‘With us the wheat 
crops are very poor, but on the height (Liebig’s plot) they 
have harvested three fuder of rye twelve simmer, while I 
from three fuder of the best rye, have only got five simmer. 
