C 72 ] 
the ashes, which it calories to the vessels in waiting,^ 
and receives the price ; a considerable revenue is 
derived from this object, and this tax is clear gain 
to the rich, whose servants would receive the ashes 
as with us, as a perquisite, and burn a proportioiia- 
bly greater quantity of fuel to increase it. 
From the place where they were burning the 
earth I proceeded to the oar bed, which I examin¬ 
ed and found the earth very similar to what I have 
seen on my own estate in Clermont, and which may 
indeed be found in many of our black meadows. I 
send you a sample of the earth as a guide to search 
it at home ; many of our fellow labourers, will, I 
•dare say, know where to find it ; I also send a sam¬ 
ple of the ashes, I would recommend to the soci¬ 
ety to have some experiments made on this inter¬ 
esting subject : first, by searching for a similar 
earth, drying and laying it in beds of about a foot 
thick and burning it, occasionally stiring it with a 
rake—^then pounding and sifting it in a lime sieve 2 
if the earth should be too inflamable perhaps a mix¬ 
ture of lime, which it would convert into gypsum, 
or wood ashes would be found useful. Second, by 
trying the effect of diluted vitriolic acid as a ma¬ 
nure singly, or mixed with ashes. Third, if it is 
clear that this acid is a fertili 2 ;er, to endeavor to find 
one that is still cheaper, and that might perhaps be 
found still better, as it had already composed a con¬ 
stituent part of vegitables. The pyro ligneous 
?icid may be obtained at almost no expense, by coiif 
