THE CULTIVATOR 
87 
by this ingenious practical philosopher, and which tire founded on the princi¬ 
ples of science, and on numerous experiments:—1. The throat of the chimney 
should be perpendicularly over the fire; as the smoke and hot vapor which rise 
from a fire naturally tend upwards. By the threat of a chimney is meant the 
lower extremity of its canal, where it unites with the upper part of its open 
fireplace. 2. The nearer the throat of a chimney is to the fire, the stronger 
will be its draught, and the less danger of its smoking; since smoke rises in 
consequence of its rarefaction by heat, and the heat is greater nearer the fire 
than at. a greater distance from it. But the draught of a chimney may be too 
strong, so as to consume the fuel too rapidly ; and. therefore, a due medium 
must be fixed upon according to circumstances. 3. That four inches is the pro¬ 
per width to be given to the throat of a chimney, reckoning across from the top 
of the breast of the chimney, or the inside of the mantle to the back of the 
chimney; and even in large halls, where great fires are kept up, this width 
should never be increased beyond or 5 inches. 4. The width given to 
the back of the chimney should be about one-third of the width of the opening 
of the fireplace in front. In a room of a middling size, thirteen inches is a good 
size for the width of the hack, and 3 times 13 or 39 inches for the width of the 
opening of the fireplace in front. 5. The angle made by the back of the fire¬ 
place and the sides of it, or covings, should be 135 degrees, which is the best 
position they nan have for throwing heat into the room. 6. The back of the 
chimney should always be built perfectly upright. 7. Where the throat of the 
chimney has an end, that is to say, where it enters into the lower part of the 
open canal of the chimney, there the three walls which form the two covings 
and the back of the fireplace should all end abruptly , without any slope, which 
will render it more difficult for any wind from above to force its way through 
the narrow passage of the throat of the chimney. The back and covings 
should rise 5 or 6 inches higher than the breast of the chimney. 8. The cur¬ 
rent of air which, passing under the mantle, gets into the chimney, should be 
made gradually to bend its course upwards: by which means i 1 will unite qui¬ 
etly with the ascending current of smoke. This is effected with the greatest 
ease and certainty, merely by rounding off the breast of the chimney, or back 
part of the mantle, instead of leaving it flat or full of holes and corners. Fig. 
28 shows the section of a chimney on the common construction, in which d e 
is the throat. Fig. 29 shows a section of the same chimney, altered and im¬ 
proved, in which d i is the reduced throat, four inches in the direction of d i, 
and thirteen inches in aline parallel to the mantle.— Dick. 
THE SHEEP .—(Continued from page 68.) 
PERIODICAL DECIDENCE OF WOOL AND HAIR. 
Wool is distinguished from hair by the manner in which it separates from 
the animal, and is renewed. Most of those animals whose covering is hair, 
renew their coat at least once in the year: in the horse it is shed twice— 
in the spring and the autumn. This is evident enough in the colt, and in the 
farmer’s horse, whose coat is often exposed, almost as much as in a state of 
nature, to the influence and occasional inclemency of the seasons; but when 
they are domesticated and stabled, the process is far from being regularly 
conducted ; it appears to be in a manner suspended, but it is, in fact, going 
on all the year round. In the deer it has its regular period; less so in the ox, 
and least of all in the dog: but in all of them, when the pulpy substance 
at the root of the hair ceases to be supplied, and, losing its support, the 
hair is detached and foils off. the different fibres separate, as it were, one 
bv one. The old hair and the new remain together for a season, and no part 
of the skin is left at any time bare. The period of the reproduction of the 
hair is very often connected with disease, and almost invariably so with loss 
of power. The human being, however, is not, like these quadrupeds, subject 
to an annual renew’al of the covering of the skin; the hair once produced, 
continues to grow for many a year, perhaps for life, by prolongation from the 
root. 
There is considerable difficulty respecting this change of external covering 
in the sheep. It has been commonly believed that there isa periodical moult¬ 
ing, or separation from the old fleece from that which is growing underneath; 
and there is no doubt, that the greater part or the whole of the fleece of the 
more neglected breeds, begins about the commencement of summer, to detach 
itself from the pelt; and much of it would be lost if its separation were not 
anticipated by the application of the shears. On the other hand, the wool of 
the lamb that was dropped in the winter or spring, shows no disposition to 
separate, but continues to grow; and the observation of this has introduced a 
practice, the advantage of which will hereafter be considered, of leaving the 
hogget wool, for the first sixteen or eighteen months, to acquire additional length 
of staple. The Merino sheep affords a singular proof how easily the annual 
change of the fleece—if annual change there is—may be suspended in the do¬ 
mesticated state ot that animal. Lord Western has retained the wool of the 
Merino, without the slightest disposition to separate, during three years. The 
experiment was also tried at Rambouillet, and the fleece remained on firm and 
healthy during five years. It had attained its utmost growth at the fourth year, 
when it was 13 inches long; but it had no disposition to separate from the skin, 
and probably it would not have fallen off during the life of the sheep. There 
were not merely a lew cases of this, but the experiment succeeded in every 
sheep on which it was tried. 
THE FORM OF THE FIBRE. 
The fibre of the wool, having penetrated the skin and escaped from the yolk, 
is of a circular form, (varying in diameter in different breeds, and in different 
parts of the same fleece,) generally larger towards the extremity and also to¬ 
wards the root, and in some instances very considerably so. 
The filaments of white wool, when cleaned from grease, are semi-transpa¬ 
rent; their surface in some places is beautifully polished, in others curiously 
encrusted, and they reflect the rays of light in a very pleasing manner. When 
viewed by the aid of a powerful achromatic microscope, the central part of the 
fibre has a singularly glittering appearance. Very irregularly placed minuter 
filaments are seen branching from the main trunk, like boughs from the prin¬ 
cipal stem. This exterior polish varies much in different wools, and in wools 
from the same breed of sheep at different times. When the animal is in good 
condition and the fleece healthy, the appearance of the fibre is really brilliant; 
I but when the sheep has been half-starved, the wool seems to have sympathized 
with the state of the constitution, and either a wan, pale light, or sometimes 
scarcely any, is reflected. 
If any great and injudicious alteration has taken place in the management of 
the sheep during any period of the year, although the fibre may continue to 
' preserve a portion of its brilliancy, a very considerable difference in its ap- 
pearance will be immediately detected. Some have said (but our microscopi- 
! cal observations on wool will show that to be scarcely possible,) that occa¬ 
sionally the change in the structure of the fi ament is so great that a certain 
length yf hair is interposed between two portions of wool; often, however, 
close observation will discover a remaokable diminution of the bulk of the 
fibre, n withered and opaque surface, and a partial loss of the characteristic 
serrations and cones. These wools are much deteriorated in value; they will 
give way under the operation of the comb, and w'ill injure or spoil the manu¬ 
facture in which they are used. A microscope is not always needed in order 
to discover this change in the wool; bxt if such an instrument is at hand—and 
no wool-stapler or wool-grower should be without one—the semi-transparency 
of the wool, and rhe opacity of the hair—and the roundness and fulness of the 
healthy fibre, and the withered appearance of the joint, or breach, as it is called, 
will form a singular contrast. 
As a general rule, the filament is most transparent in the best and most use¬ 
ful wools, whether long oj short It increases with the improvement of the 
breed, and the fineness and healthiness of the fleece; yet it must be acknowl¬ 
edged that some wools have different degrees of transparency and opacity 
which do not appear to affect their utility or value. In the Vigonian wools the 
staple is nearly opaque, but the wool is remarkable for itssmoothness and silky 
texture. It is, however, the difference of transparence in the same fleece or 
in the same filament that is chiefly to be noticed as impairing the value of the 
wool. 
Mr. Luccock speaks of some families of sheep in which the pile is flat and 
smooth, like a small bar of finely polished steel. A few filaments of this kind, 
the author has observed, but they have seldom been sufficiently numerous to 
be regarded as constituting the character of the fleece, and in the decided num¬ 
ber of cases, the appearance has been altogether deceptive. It has arisen from 
the direction in w hich the light has fallen on the object; and the lamp being 
raised or lowered, or drawn on one side, the seemingly flattened bar assumed 
its circular but withered form. These sheep had been cruelly neglected, the 
secretion of the woolly fibre had never been healthily discharged, and the 
whole fleece, or a great portion of it, might be said to have assumed a breachy 
character. 
SIR WILLIAM JONES. 
This man, so remarkable for his literary labors, for industry, and methodical 
habits, never was known to depart from the rules contained in a few simple 
maxims, which he often repeated. 
The first was, never to neglect any opportunity of improvement which pre¬ 
sented itself. 
The second was, that whatever had been attained, was attainable by him; 
and that therefore the real or supposed difficulties of any pursuit formed no 
reason why he should not engage in it w ith perfect confidence of success. 
The third was, not to be deterred by any difficulties which were surmount¬ 
able, from prosecuting to a successful termination that which he had once de¬ 
liberately undertaken. 
It was by attending to these maxims, that he was enabled to accumulate a 
vast mass of knowledge, and to accomplish labors of a magnitude seldom sur¬ 
passed. 
Opportunity has hair in front—behind she is bald. If you seize 
her by the forelock, you may hold her, but if suffered to escape, you 
cannot catch her again. 
We seldom find persons whom we acknowledge to be possessed of 
good sense, except those who agree with us in opinion.— Rochfau- 
cault. When such occasions do occur, our self-love always induces 
a decision in favor of their judgment. 
