834 = 5^5 Influence of Chemical Discoveries on 
fit for downward intermittent filtration can be acquired, thf 
sewage, partially clarified by subsidence, may be dealt witt 
partly in the way of ordinary irrigation, with a view of realising 
a profit in growing Italian rye-grass and other crops, and parth 
by way of concentrated or downward intermittent filtration 
with a view of getting rid of the excess of sewage for whicl 
the sewage farmers cannot find a profitable use. 
3. When such land cannot be procured, recourse should be hat 
to the purification of sewage by chemical precipitating agents. 
4. Town sewage, in my opinion, far from being a valuabh 
agricultural commodity, is a nuisance, which can only ir 
exceptional circumstances be turned to profitable account. I 
cannot therefore be reasonably expected that the agriculturis 
should have to pay the costs which the disposal of sewage entails 
and which ought to be defrayed by the ratepayers, who enjo\ 
the luxury and comfort of a system of water-closets am 
thorough town drainage. 
CHAPTER IV. 
Improvement of Permanent Pastures. > 
Recent atten- PERMANENT pastures in England were much neglected previoui 
tion to the I860, little or nothing in the way of improvements havin; 
been done until then to most grass lands. During the last si: 
or eight years, however, owing partly to the good prices of dair 
produce and of store stock and butcher's meat, more attentioi 
has been paid to the improvement of permanent pastures. In ! 
report on the application of chemistry to agriculture, it would bi 
out of place to enter into details as to the means whereby worn 
out old pastures, and grass land in general, have of late years beei 
so much improved. The subject is introduced into this repor 
mainly for the purpose of pointing out that the improvement 
which have recently taken place in England are due in a grea 
measure to the laborious and long-continued experiments o 
Eiperiments at Messrs. Lawes and Gilbert. The experiments to .which I spe 
Rothamsted. cjally refer were carried out in Mr. Lawes's Park at Rothamsted 
with a view of studying the influence of different manurin; 
agents on the mixed herbage of permanent grass-land. They wer 
commenced in 1856, and have now been continued over a periot 
of twenty years. At the commencement of this long experi 
mental period, the herbage was pretty uniform over the whol 
area selected, and included a number of plants, of which abou 
fifty species var}' so prominently as to be readily recognised in 
fair average sample of hay grown without manure. Abou 
I 
