1882.] 
AMEBICAN AGBIOULTUBIST. 
107 
nutritive processes, and that they are not 
“ burnt,” as in a furnace to keep up the 
animal temperature. In fact there is no evi¬ 
dence that anything like a combustive oxy- 
dization of the fluids or tissues takes place 
in any part of the system. The oxygen taken 
in by the lungs in the process of respiration, 
must now be looked upon as a nutritive ele¬ 
ment, or in other words as food that is 
essential to the healthy activity of all the 
tissues of the body. In connection with 
other nutritive materials, finding their way 
to the blood through the digestive organs, it 
is stored up and takes part in the formation 
of the organs of the body and aids in the 
performance of their several functions. The 
carbonic acid, that is exhaled as an excretory 
substance by the lungs, is not formed directly 
by a simple union of oxygen and carbon, as 
was formerly supposed, but is one of the pro¬ 
ducts of disintegration, or splitting apart, as it 
were, of the tissues which are constantly un¬ 
dergoing the process of decomposition and re¬ 
pair, that is characteristic of all living tissues. 
In the taking in of oxygen, by the lungs, and 
the exhalation of carbonic acid, we therefore 
see but the beginning and the end of a long- 
series of changes and transformations of or¬ 
ganic materials that constitute the entire 
activities of the system. 
The fallacies of the ‘ ‘ combustive theory ” 
of respiration have undoubtedly been ob¬ 
stacles to the proper understanding of nutri¬ 
tive processes, and the relative value of the 
constituents of foods. Foods are composed 
of proteids, or albuminoids, carbohydrates, 
fats, and inorganic or mineral matters. The 
proteids, or albuminoids, as they are often 
called, are substances that resemble albumen 
in composition, as various forms of albumen, 
casein, fibrin, legumin, etc., and they all 
contain nitrogen. The proteids therefore 
constitute the nitrogenous group of nutri¬ 
ents. The carbohydrates are the substances 
that resemble starch in composition, as cellu¬ 
lose or woody fibre, starch, sugar of various 
forms, of gums, etc. As the carbohydrates and 
fats contain no nitrogen, they are often called 
the non-nitrogenous group. The part taken by 
each of these nutritive elements, cannot, in 
the present state of our knowledge, be fully 
traced, but they all seem necessary to form 
what may be called a perfect food. The 
proteids are essential in the construction or 
building up processes of all tissues. Every 
cell of the animal body, whether of muscle, 
or nerve, or fat, or of secreting glands to pre¬ 
pare the various digestive fluids, or of the 
excretory glands that tlirow off the waste 
products of the various organs, must have a 
supply of proteids, or it cannot perform the 
functions required as a part of living tissue. 
Even fat itself may be formed from the pro¬ 
teids, and it seejns probable that the butter 
globules, or fat of the milk, is largely, and 
perhaps almost entirely formed by a trans¬ 
formation of proteid materials. Voit, from 
experiments with dogs, reached the con¬ 
clusion that all fat was formed at the expense 
of proteids, even in cattle and swine, but 
Lawes and Gilbert, in their extended and ac¬ 
curate feeding experiments have proved that 
at least 40 and in all probability more t.hq. n 
50 per cent of the fat laid up by pigs on a 
good fattening diet, must have been formed 
from carbohydrates. An animal can live for 
some time on an exclusive diet of proteids, 
as they seem to have the power of taking 
upon themselves the parts more economically 
performed by the carbohydrates and fats, in 
addition to their own peculiar functions. 
[The discussion of this important subject 
may be resumed another month.— Eds.] 
Silk Worms and Their Food. 
The Morus multicaulis craze of about fifty 
years ago so disgusted people with every¬ 
thing related to silk raising, that whatever 
progress had been made before that time 
went for nothing. Within a few years there 
has been a renewal of interest in silk culture, 
which, if allowed to develope in a healthy 
manner, will lead to good results. As indi¬ 
cations of this revival, we note : The Special 
Report of Prof. C. V. Riley, Entomologist 
to the Department of Agriculture, published 
in 1879 ; and the formation of a Society in 
Philadelphia for the promotion of Silk Cul¬ 
ture. Before this reaches our readers, this 
Society will have held an exhibition, and 
awarded premiums for the best lots of co¬ 
coons raised by women in Pennsylvania, and 
by colored women in any State. This Society 
touches the key-note of the success of silk 
culture in this country, and the same is advo¬ 
cated by Prof. Riley in the Report- just re¬ 
ferred to, i. e., that silk culture must be a 
; family industry ; the care and feeding of the 
worms must be done by the women and 
children, and by others whose old age or 
feeble condition do not allow of active labor. 
Silk culture can not be carried on by com¬ 
panies with hired labor, but to gain a perma¬ 
nent foothold and be profitable, it must be 
accepted as a part of the farm work, just as 
are the care of poultry or bees, the making of 
butter and cheese, or in some localities the 
production of maple sugar. Carried on in 
this manner, the required labor will not be 
taken from any other industry of the farm, 
as it may be done by those unfitted for hard 
work, and while the annual income in each 
case may not be very large, it may be an im¬ 
portant addition to the family purse, and in 
the aggregate add largely to the prosperity of 
the community. That a renewed interest is 
now felt in Silk Culture is shown by the in¬ 
quiries that come to us as to where the eggs 
of the silk-woan may be procured. These 
letters often indicate that the writer has not 
considered the more important question of 
the food supply for the worms that are to be 
hatched from the eggs. We shall gladly en¬ 
courage a healthy development of this indus¬ 
try, and are sure that the best service we can 
at present render to those who are desirous 
of undertaking silk culture, is to direct their 
attention to the matter of food for the worms. 
This must of couise precede everything else. 
The true silk-worm can prosper only upon 
the leaves of some kind of Mulberry ; it does 
fairly well on the leaves of the related Osage 
Orange, and the worms, when very young, 
may be kept alive on Lettuce leaves, still the 
Mulberry is the best food. Upon many 
places there are old Mulberry trees, left as a 
memento of the Moro-mania, as the multi¬ 
caulis speculation has been called. Where 
such trees exist they will afford a supply of 
food for a beginning, and to raise a stock of 
worms to lay eggs for future operations ; but 
the labor of collecting leaves from old trees 
is too great to be profitable. Where there 
are already established hedges of the Osage 
Orange, the raising of silk-worms may be 
undertaken, as with proper care success will 
follow. But if a food supply is to be provided, 
let it be some form of the White Mulberry 
{Morus alba). The French writers enumer¬ 
ate twelve varieties of the White Mulberry, 
and several of Morus multicaulis, but this 
last is by the best authorities regarded as a 
variety of the White Mulberry, and so is the 
Moretti, another kind valued as food for silk¬ 
worms. The Mulberry is grown from the 
seed, from cuttings, and by layers, etc. 
We need consider only the first two meth¬ 
ods. Our dealers in tree seeds offer the seeds 
of the common White Mulberry, the Multi¬ 
caulis, and the Moretti, the last two varieties 
coming sufficiently true from seeds. The 
seeds may be sown like those of ordinary 
garden vegetables, in good soil in early spring 
in drills 18 inches apart, and when large 
enough, the young plants thinned to three 
inches and kept free from weeds. They are 
usually left in the seed-bed for two years, 
mulching the ground heavily at the approach 
of winter; after which they are set in the 
plantation. Where cuttings can be procured, 
this is the best method of raising the trees. 
Shoots of the previous year’s growth are 
made into cuttings about 6 inches long, mak¬ 
ing the cut just below a bud ; these may be 
set in the fall, or early spring, putting them 
3 or 4 inches apart in the row, leaving but 
one bud above ground ; the rows should be 
far enough apart to work with the cultivator. 
The next year the yoimg trees may be set 
where they are to grow. Whether seedlings 
or rooted cuttings are planted, they may be 
set out in hedge rows, or a piece of ground 
be given up to the plantation. In either case 
they should be 6 to 10 feet apart, and are to 
be kept low, in order to allow of the easy 
gathering of the leaves. The main stem 
may be but a foot or so high, or 6 feet high, 
as circumstances require. When the trunks 
are of the last-named hight, the trees are 
treated as described for Pollard Willows, in 
an article on page 110. 
A “Sagging Bar” for Gate. 
Mr. J. Meyer, La Salle Co., Ill., sends a 
sketch and description of a device for over¬ 
coming the sagging of a gate. The hinge- 
post of the gate-frame extends somewhat 
A REMEDY FOR A SAGGING GATE. 
above the upper bar of the gate. A board is 
fastened to the top of this post, a, which 
runs downward to b, near the middle of the 
upper cross-bar, and then connects with a 
short double band—one on each side of the 
long board—which is provided with a bolt 
fitting into notches, c, cut in the under side 
of the upper bar of the gate. The form of 
the double-latch piece, with its bolts, and its 
attachment to the board is shown at d. 
