4-18 
AMERICAN AGKICULTURIST. 
[November, 
been verified ; viz., success in artificial incuba- 
tion depends upon a close imitation of nature. 
In making an incubator, economy of beat is 
an important matter; and we must consider also 
ease of management. Tbe writer, in examining 
into the structure of some of the most approved 
incubators, lias hit upon a simple plan which 
avoids tbe patented features of those he is famil- 
iar with atd will probably be entirely efficient. 
A front view of this is shown in fig. 3. E, E, 
E, are three boxes of wood, painted or pitched 
on the inside and painted on the outside; filled 
with moist earth and having the eggs partly 
Fig. 5. — STRUCTURE OF THE EGG. 
imbedded in the earth. Over these boxes, fitting 
saddle-wise upon each of them, is a heater, pref- 
erably made of copper or brass. The two 
spaces between the boxes are about 4 inches 
wide, and here the lamps are placed for heating. 
Little screens are soldered upon each side of the 
portion exposed directly to the flames, to shield 
the boxes from the direct influence of the lamps. 
By raising either end of the heater a very little, 
one of the end boxes, or the middle one may be 
withdrawn at pleasure. In the top of the heat- 
er there is a ventilating tube always open, a 
place for filling and emptying, and a tube for 
receiving a thermometer in a cork. When the 
boxes are in place there is a free space over the 
eggs in front, and a round ventilating hole at 
the rear, as shown in fig. 1, and the section 
through the line A, B. (fig. 2.) 
This is sufficient provision for ventilation ; in- 
deed, more than is needed, for the front opening 
would probably need to be loosely filled with 
wool or cotton. We suggest the idea of having 
several small flames or lamps rather than one, as 
being much more easily regulated, and lessliable 
to cause sudden changes of temperature from ac- 
cidents. The form is immaterial. The one shown 
in figs. 3 and 4, would doubtless work well. It 
consists of a one-inch gas pipe,drilled to take sev- 
eral wick tubes, and communicating with a foun- 
tain which keeps it constantly full to the same 
level, on the well-known principle employed in 
Fig. 6. — THE EGG ABOUT THE SIXTH DAT. 
the German student-lamps. Good sperm oil 
or the best kerosene should be used. The eggs 
ought to be exposed to a temperature of about 
102°. In most incubators they are in contact 
with warm air simply, which is exceedingly 
sensitive to changes, and difficult to keep up to 
the proper point without having the water in 
the heater too hot. We propose to avoid this 
trouble and imitate nature still more closely, 
by providing little silk bags loosely filled 
With fine, copper turnings, to lie upon the eggs 
and to touch the heater also. The copper 
will remain of nearly equal temperature all 
over, and will bring the heat more tangibly in 
contact with the top of the eggs than can be 
effected by sand or in any way we know of. 
■ •»-* a Bfc i » » 
Outlet for an Ice-Pond. 
Considering all the trouble we had last win- 
ter to get ice, and the prices we have had to 
pay, we may well look out beforehand, that 
our arrangements are made for securing a stock 
next winter. The coldest water lies at the bot- 
tom of a pond in summer ; not so in winter. 
Then the wannest is at the bottom, for as soon 
as the temperature of the pond falls below 40°, 
the coldest water stays on the surface, and the 
water below remains at 40°, until it is either 
warmer, or becomes colder through the freezing 
of that above. Warren Leland, of Highland 
Farms, Westchester Co., N. Y., reports, that be 
doubled the thickness of his ice, by having the 
outlet made at the bottom instead of at the top, 
thus drawing off the warmest water instead of 
the coldest. He sent this statement to the pa- 
pers last 3'ear, too late to be of any use to our 
readers. It is so in accordance with the facts 
above mentioned, that we do not doubt the cor- 
rectness of Mr. L.'s conclusions. — He says : "The 
usual way of constructing outlets of ice-ponds 
is by an overflow at the surface. In this way 
the top of the water is always in motion; and 
after ice has formed, the warm water from 
springs, and underdrain flowing along its under 
surface, prevents its thickening. To obviate 
these difficulties, the outlet should be from the 
bottom of the pond — leaving the surface un- 
disturbed to cool and freeze more readily, by 
the cold air and action of the ice. This style 
of outlet also tends to keep the water free from 
sediment. It is easily constructed, by having 
an iron or wooden tube leading directly from 
the bottom of the pond, or by a flume, arranged 
to draw from the bottom. Having in this way 
doubled the thickness of ice on my pond, I wish 
through your columns to give my brother far- 
mers the benefit of my experience." 
^ i Mil 1 * 
The Field-Roller. 
It is rare to find a field-roller upon the form 
and yet upon many forms it would pay for it- 
self every season. The implement as turned 
out from the factory is rather expensive, cost- 
ing about 80 dollars. This is a large sum to 
pay for an article most formers have never 
used and never felt the need of. The necessity 
of it is not so obvious as that of the mowing 
machine, and yet it has its place in the routine 
of our labors. It is the best implement for 
making a smooth surface for the meadow; a 
matter of great importance for the mowing ma- 
chine. It should follow the bush harrow always 
in the spring, when the land is laid down to 
grass. And if the land is wet, and the grass 
roots have been thrown out by frost, the roller 
will press many of them back again and make 
a smooth surface. It is also of great service in 
breaking bard lumps, when the land is plowed 
for hoed crops, or for spring or winter grain. 
These lumps are a severe obstacle to the progress 
of crops in the soil, and whatever aliment they 
contain is lost to the growing crop. The roller 
is a good pulverizer. Then in a dry time it 
greatly assists in the germination of seeds. 
Wheat,rye,and other grains come up much better 
for the pressure of the soil around them. Then 
the labor of cultivation is economized bv having 
the field laid as smoothly as possible. You can 
see the rows very distinctly, and begin the cul- 
tivation sooner, and bring the cultivator much 
nearer the growing plants, leaving much less la- 
bor for the hoe. This makes a large saving in the 
item of labor. It is of still greater service in dis- 
posing of the small stones in the gravelly loams 
on many fields ; it will bring all of these on a 
level with the surface and put them below the 
cut of the mowing machine. This saves the 
disagreeable labor of picking stones, which has 
probably weaned more boys from the form than 
any other work. We have found so great ad- 
vantage from the use of the roller, that we should 
not know how to dispense with it. If a man has 
capital, let him by all means get the best pat- 
tern, with cast-iron cylinders. If not, he can 
make a wooden roller that will do good work 
and last many years, with very little outlay of 
money. From a large tree, three feet through 
at the but, cut off a section of 8 feet, make it as 
near cylindrical in shape as possible, drive in 
two large iron pins exactly in the center, hang 
it in a frame and put on a pole for the team. 
A roller made of hewn stone is still better, for 
it is heavier and more durable. Get a roller 
if you have to make it with your own hands. 
How much Hay will Sheep eat in Winter ? 
Harry Taylor asks " how much clover hay 
will a sheep eat per day ?" The general answer 
is from 2'| 2 to three per cent of live weight. A 
flock of full-grown Merino sheep averaging 80 
lbs., could probably be wintered on 2 lbs. 
of hay per head per day. This would 
keep them in a healthy condition, but 
it is not likely that they would increase in 
weight. The food would all be used to sustain 
the vital functions, and for the growth of wool 
and secretion of yolk. Full-grown English 
sheep, averaging, say 150 lbs., would probably 
eat 4 lbs. of hay per day and would increase in 
weight 1 lb. per week. In the case of ewes in 
lamb, the increase would be in the growth of 
tbe foetus and in fat and other material stored 
up for the use of the lamb after birth. The 
quantity and quality of the milk are influenced 
very much by the quantity and quality of the 
food supplied during the period of gestation. 
The long-wooled, or South-Down, ewes should 
have all the clover hay they will eat during 
the winter; or if a portion of straw is fed 
instead of hay, the difference in the amount of 
nutriment should be made up by allowing a lit- 
tle grain ; say l l | 2 lb. of hay, l'|n lb. straw 
and 1 lb. oats, peas, corn, or oil-cake. This 
would keep such sheep in splendid condition, 
and insure strong, healthy lambs and an abun- 
dance of milk. Last spring we had a Cotswold 
lamb that weighed 12 1 | a lbs. the day it was 
born and in two weeks from that day it weigh- 
ed 25 lbs. At six months old it weighed 120 
lbs.; of course breeding had something to do 
with it; but this rapid growth of a young 
lamb is caused by a liberal supply of rich milk ; 
and this is obtained not only by feeding the ewe 
liberally while she is suckling the lamb, but 
also by feeding her liberally during the period 
of gestation, thereby enabling her to store up 
food for the use of her lamb or lambs. Young, 
growing, Merino sheep will probabty eat 3 
lbs. of clover hay per day fir every 100 lbs. 
of live weight; that is to say, a lot of Merino- 
lambs eight or nine months old and averaging 
50 lbs., would eat l'j 2 lb. of clover ha}' per 
day and gain from nothing to half a pound each, 
per week. On the other hand, a lot ot well-bred 
