|| 
applicable of counter-irritants, and can be used in 
situations and under circumstances where these 
other remedies are inadmissible. They are em- 
ployed more commonly on the Continent than in 
Britain; but have of late years acquired increas- 
ing favour among British farriers. They serve 
particularly well in poll-evil, fistulous withers, 
and other ulcerative processes,—in chronic en- 
largement of the joints and ligaments and other 
parts,—and in all abscesses and diseases of the 
navicular region. In every case, a seton must 
be cleaned and moved daily, and dressed with 
common resin ointment; and in cases of their 
application to a sinuous track for the purpose of 
inflaming it, they must be renewed twice a-day, 
and moistened each time with oil of turpentine 
or tincture of aloes and benjamin or some similar 
stimulant. 
SETTER. See Doe. 
SEWERAGE. The drainage of towns. It 
comprises the rain water from the streets, the 
silty portions of mud from the yards and cause- 
ways, the foul water from kitchens, the refuse 
water of manufactories, the cleanings of water- 
closets, and, in general, all the filth and salts 
and organic matters which are not readily re- 
moveable in carts or waggons; and it is therefore 
very rich in at once variety, kind, and power of 
manurial ingredients. Even though it contained 
nothing more than nearly all the excrements, 
both liquid and solid, of the whole population, 
both brute and human, and though it held these 
in a state of very great dilution in otherwise 
useless water, it would be a highly valuable 
liquid manure; but it also contains other em- 
inently fertilizing substances, and combines them 
and the excrements in proportions suited to the 
average wants of almost all field crops, and holds 
all in a state of comparatively great concentra- 
tion,—and it is therefore well fitted to serve as 
a succedaneum for farm-yard manure, or rather, 
in fact, is in itself the very best of all general 
manures. The analysis of a specimen of it is 
given near the close of the article MANURE; a 
good notion of its silty and least valuable por- 
tions may be obtained from the article Potice 
Manure; a large instance of its tried power as 
| a liquid manure for grass lands is mentioned in 
the article IRrication ; and striking ideas of the 
fertilizing energy of its most active and charac- 
teristic ingredients may be obtained from the 
articles Liguip Manure, Urine, Nieut Sor, Ex- 
CREMENT, and Anima MAnurgs. 
A statement of the vast annual loss of manurial 
matters sustained by Britain, in several ways, 
but chiefly in the escape of sewerage to rivers and 
| the sea, is made in the last section of our article 
Manure; and the following statement was made 
by a distinguished agricultural writer seven years 
ago, and has been abundantly borne out by more 
recent investigations respecting the condition of 
the metropolis:—“By carefully conducted ex- 
periments and very accurate gaugings, it has 
SEWERAGE. 
been found that the chief London sewers convey | 
daily into the Thames about 115,000 tons of 
mixed drainage, consisting on an average com- 
putation, of 1 part of solid and 25 absolutely 
fluid matters; but if we only allow 1 part in 30 
of this immense mass to be composed of solid 
substances, then we have the large quantity of 
more than 3,800 tons of solid manure daily 
poured into the river from London alone, con- 
sisting principally of excrements, soot, and the 
debris of the London streets, which is chiefly 
carbonate of lime; thus, allowing 20 tons of this 
manure as a dressing for an acre of ground, there 
is evidently a quantity of solid manure, annu- 
ally poured into the river, equal to fertilizing 
more than 50,000 acres of the poorest cultivated | 
land! The quantity of food thus lost to the 
country by this heedless waste of manure is 
enormous; for only allowing one crop of wheat 
to be raised on these 50,000 acres, that would be 
equal to the maintenance (calculating upon an 
average produce of 3 quarters of wheat per acre) 
of 150,000 persons. London, too, is only one huge 
instance of this thoughtless waste of the agricul- 
tural riches of the soil of England; from every 
other English city, every town, every hamlet, is 
hourly passing into the sea a proportionate waste 
of liquid manure; and I have only spoken of the 
solid or mechanically suspended matters of the 
average; the absolutely fluid portion is still rich 
in urine, ammoniacal salts, soda, &c., when all 
the mechanically suspended matters have been 
separated from the other portion. According to 
very careful experiments, this fluid part often 
contains 16 per cent. of animal matters, salts, 
&c., intimately or chemically combined with the 
water.” The waste of sewerage, also, is a tre- 
mendous outspread of noxious exhalations and a 
dreadful polluting of useful streams, to the effect 
of marring the public comfort, injuring the 
public health, and constantly keeping up epide- 
mics and pestilence; so that any measure which | 
completely saves and economises sewerage for | 
the purposes of manuring, at the same time acts 
as a mighty conservator of the life and well-being 
of both man and beast. 
A great enterprise was recently commenced, 
by what is called the Metropolitan Sewerage 
Manure Company, for appropriating all the sew- 
erage of London to manuring purposes; and this, 
it is to be hoped, will not only prove highly com- 
pensating to the parties interested in it, and 
eminently beneficial to the farmers and the 
market-gardeners who may avail themselves of 
it, but be speedily imitated in every city and 
considerable town of the empire. The whole 
plan is nearly a counterpart of that by which 
the city is supplied with water and with gas. 
Between the new house of Parliament and Stan- 
ley-bridge run two great sewers, the King’s 
Scholars’ Pond and the Ranelagh, both of them 
open, and some five or six small ones, The com- 
pany makes an intercepting sewer from the first 
