400 
AMERICAN AGRICULTURIST. 
[November, 
but little earth to be removed above it; it is 
split into small masses, making a great saving 
of labor and powder ; it is of remarkable rich- 
ness and purity, and is practically inexhaustible. 
Prof. S. P. Duffield, of Detroit, has analyzed it, 
and gives the following results: Lime, 36.08; 
Sulphuric Acid, 5425; "Water, 8.89; Impurities, 
0.78. The use of plaster in this State is rapid- 
ly on the increase, as its value becomes better 
understood. About 14,000 tons from the mine 
referred to were sold last year, and the sales 
are much larger, thus far, the present season. 
We have seen the idea advanced that the use 
of plaster is likely to exhaust soils. There is 
very little ground for this fear, though the use 
of small quantities annually, without other ma- 
nure, and without proper tillage, would tend 
finally to exhaustion. In plaster we add only 
two articles of plant food, namely, lime and 
sulphuric acid. The effect of plaster upon the 
soil is said to be stimulating, that is, it enables 
larger crops to be secured, than could be 
removed otherwise, without the use of 
much manure. "With these large crops 
much plant food is taken from the soil, 
and in time this will tell against the land, 
if it is not in some way made good by 
manure. It is found that grazing lands 
are for many years increased in produc- 
tiveness by its use. The plaster brings 
in clover, and stimulates the growth 
of all the grasses. Exhausted lands 
have been brought up to a high state 
of productiveness by the use of plaster 
and grazing alone. The roots of the 
plants strike down into the soil with 
greater vigor, and a good portion of the 
inorganic matter of the soil, which would 
constitute their ashes, if burned, is re- 
turned to the land in the droppings 
of the stock. Over a very large portion 
of our country, remote from the sea, plaster 
is no doubt the cheapest fertilizer that can 
be applied to pastures. It is easily transported, 
and a small application of two bushels to the 
acre broadcast on the surface has usually all the 
immediate effect of a much larger quantity. 
fore it was plowed. All dead furrows are avoid- 
ed, and time is saved in the turning of the team 
at the ends of the lands. These plows are exhib- 
ited in much larger numbers at the fairs, and 
are coming rapidly into favor. They are made 
of any desirable pattern, embrace most of 
the good points of other plows, and have the 
advantage of turning the furrow to the right or 
to the left, according to the wish of the plowman. 
The Manufacture of Fish Oil and Guano. 
The use of fish as a fertilizer in this country 
is of early origin. The Aborigines are said to 
have understood their value and to have applied 
them to the old fields where they raised their 
limited crops of Indiau corn. The colonists 
along the shore began to use them as soon as 
their exhausted farms showed the need of fer- 
tilizers. Large seines were owned by compa- 
nies of shore farmers, and ever)' interval in the 
nets, 
The Side-hill or Swivel Plow. 
This implement, invented to avoid the diffi- 
culty of turning furrows up hill, is likely to be 
as great a boon to the plain as to the hill-side. 
It affords great facilities to the farmers who have 
uneven soil to cultivate. The plow turns on a 
swivel at the bottom, and the mold-board may 
be changed in a moment from one side of the 
team to the other, and held tight to its place by 
a hook. Any plowman can do this while the 
team is turning round at the end of the furrow. 
The plowing is begun at the bottom of the hill, 
and the furrow is turned alternately to the left 
and to the right, as the team moves back and 
forth. All the furrows are turned down hill, 
and the surface is left smooth as upon the plain. 
In plowing level land in the ordinary way, we 
have the disadvantage of making dead furrows 
in the middle of each land plowed, and at the 
diagonal lines where the team is turned. These 
dead furrows yield scant}' crops, and are un- 
pleasant obstructions to the mower and reaper, 
besides marring the beauty of the meadows. 
They may be mainly avoided by the use of a 
swivel plow. With this, you begin at one side 
of the field, and plow the whole length, turning 
all the furrows in one direction. At the next 
plowing you begin where you left off, reversing 
the furrows, and leaving the field as level as be- 
GKOUP OF MEXHADEN. 
cultivation and gathering of their crops was im- 
proved in fishing. The fish were applied to the 
land broadcast, and either immediately plowed 
in, or left to decompose upon the surface and to 
be turned under in the fall. This was a very 
wasteful process, but it produced such wonder- 
ful effects upon the crops that even - farmer 
within reach of the shore was eager to secure 
fish. It was not, however, until a very recent 
period that the attention of the fishermen was 
turned to the value of the oil. Perhaps the 
waning of the whale fishery and the increas- 
ing price of the oil first suggested the idea of 
extracting the oil from the fish commonly used 
as fertilizers. 
The Alausa menhaden., of Mitchell, known un- 
der the various names of Bony-fish, White-fish, 
Moss Bunker, and Menhaden, swarms along 
our coasts from the Carolinas to Maine, in im- 
mense shoals, numbering millions. The average 
weight is about a pound, being lighter in the 
spring and heavier in the fall, when they are 
most valuable for the manufacturer's purpose. 
Other fish are frequently caught in small num- 
bers in the seines, such as blue-fish, mackerel, 
bass, sturgeon, shark, and stingrays. Those 
which are not valuable for food are thrown 
into the common mass and pass through 
the factoiy. As fish guano is rapidly coming 
into use and is considered one of the best of our 
fertilizers, it will be interesting to our readers to 
learn something of the process of manufacture, 
and of the statistics of the business. Let us 
look in upon one of these establishments. 
Here, on the Long Island Sound, are plain 
substantial buildings, sheds, boilers, tanks, 
railways, and the boats and seines necessary 
for carrying on the business. The fishing is a 
business by itself. The company furnish the 
boats and seines, and take one-half of the catch 
of fish as a compensation. The rest they pur- 
chase at the market price, which is from $1.50 
to §3.00 a thousand, according to the season. 
As the yield of oil is four or five times greater 
in the fall than in the spring, the fall catch is 
much the more valuable to the manufacturer. 
As the factories are usually established near 
each other, the fishermen have the advantage of 
competition and fair prices. This company em- 
ploys four gangs of men with five boats to each. 
The seines used are from six to seven hundred 
feet long, and from eighty to ninety feet deep. 
"With such a oreadth of net-work, it is easy to 
surround a large shoal offish and capture them 
in the midst of the Sound. The seines are con- 
tracted at the bottom after the fish are surround- 
ed, and all escape is prevented. When the fish 
are drawn into a sufficiently small compass, 
they are thrown into the boats with scoop 
and the whole catch is carried to the 
factory. Here the fish are transferred to 
a carriage upon a rail track upon which 
1hey are drawn directly to the tanks, 
into which they are dropped for the pur- 
pose of steaming. The tanks hold about 
20.000 fish each. The fish are covered 
S with water, and the steam is let on by a 
SjL pipe at the bottom of the tank. After 
cooking a of an hour, the water is drawn 
jBjl off and the fish are put into cylindrical 
curbs, made of i-inch boiler iron, lined 
with stout wooden slats, and placed with- 
in a hydraulic press of 1200 tons capa- 
- city. A curb holding 3000 fish is depriv- 
ed of its oil in about five minutes. The 
average yield of oil is from 4, to 6 gallons 
a thousand. The mingled oil and wa- 
ter from the fish is conveyed by gutters 
from the press into a large wooden tank, 
where, after settling, the oil is skimmed off and 
conveyed by a pipe into the bleaching tanks, 
holding about 200 gallons each. Here it re- 
mains about 24 hours exposed to sun and rain, 
which makes it of a lighter color. It is then 
drawn off into the casks in which it is sent to 
market. At the bottom of the bleaching tanks 
a substance remains called "gurry," which is 
used for making a coarse kind of soap, chiefly 
employed in factories for cleansing wool. 
The refuse thrown out from the curb is press- 
ed a second time, and is then carried to a shed 
where it lies in a large heap until the fall or 
winter, when it is barreled or bagged for mar- 
ket. The barrels hold about 250 lbs. of the green 
scrap, and are sold by this weight, though the}' 
grow lighter by the evaporation of water. 
This coinpam - also prepares a fine ground ar- 
ticle by the following process. The green scrap 
is taken immediately from the curb and thrown 
into a picker making 1600 revolutions a minute, 
where the flesh and bones are torn into very fine 
shreds. It is then spread upon a platform a 
hundred feet square, and exposed to the sun and 
air until it is dry. By this process about forty 
per cent, of the weight is evaporated, and the 
mass is nearly pure flesh and bone. It is 
then put into a mill and ground very fine. 
This makes a concentrated fertilizer of great 
value, admirable for drilling with the seed. 
There are about one hundred of these fish oil 
manufactories along the coast from Kewbern, 
5T. O, to Mt. Pleasant Bay, Me., producing not 
far from 30,000 barrels of oil, worth about a 
half million of dollars, and about 20,000 tons of 
guano, worth nearly as much more. It is a 
thriving and increasing branch of our industry, 
and as it is immediately helpful to good hus- 
bandry, we wish it the best success. 
