HOW WOOL GROWS.

Stratford Evening Post, Volume XXXII, Issue 96, 23 April 1912, Page 3

HOW WOOL GROWS.

(By Si IT llollings, in the “Live [stock Journal.”) Since the time- when the misroscope was invented many things have boon made visible which had hitherto remained hidden from man’s ga/.e. There is no substance of which this can be said more truly than of wool. it is true that the microscope was not needl'd to tell the quality of wool; that, could he seen by the eye of an experienced hand. Before the microscope .Was used it was thought that wool 'fibres bad about them some peculiar features which helped them to hold together. This uftiuimptldil has, by pbU-iiig wool utuler the microscope, I bkui Shown to be an actual fact. By [ mici’oscopio examination the Wool libres may be so enlarged as to show quite clearly that they are serrated. Every mark on the surface and every feature of a cross section can be clearly seen. In order to explain the nature of the wool iilire and the manner of its growth, it is necessary to study the skin. The skin of the sheep, like that of human beings, is made up of four layers. These arc composed of a Vast number of cells, which are not visible to the naked eye, and are pierced by three glands. The first ol these glands is the sweat gland, winch carries off the waste matter of the body. The second is the sebaceous gland, which does not go through the skin, but terminates in the hair gland. Through this gland Hows the suint or wool yolk, the purpose of which: is to help the wool fibre to force its way through the skin. The third gland is called the hair follicle, and deserves to be specially noted. The most natural idea, which, owing to the remarkably small dimensions of the glands we arc considering, may develop in our minds, is that the hair or wool is something which is being prepared under the skin, and that after preparation it has only to force its way to the surface. This notion is altogether .erroneous. The .four follicle is really a depression in the skin.

It is well known that the human skin is constantly shedding off old dead tissue in the form of cells, and replacing them by now ones. An exactly similar process is always going on oiih'tbe sheep, but owing to the great number, of hair follicles the skin also produces a complete covering of fibres. The Hair FcSlicte. The shape of tire; hair follicle should bo specially noted, for it is ' upon this that the development of the fibre depends. Down in fids 'minute recess there is none! of that friction which carries awaynall the dead cells which are thrown off on the surface. Moreover, the warmth of the follicle prevents them from losing their vitality as soon as they become detached, yet the throwing off process 'is in constant operation, so that the follicle is kept constantly packed with detached cells which are slowly working their way towards the, opening at the top. The reader will see that the follicle is much narrower at the opening than at flic, bottom. The result of this is that, as the cells which have become detached are being forced upward by those which are succeeding them, they become more closely pressed together, and finally emerge through the month of the follicle in the form of a woolfibre. Serrations of tlie Fibre. One of the most interesting features of tin? wool fibre is its serrations. Even quite recently their presence has been denied by some who claim to be authorities on wool. This is very surprising, because the microscope reveals to us, with a clearness which admits of no denial, that the serrations actually exist. These serrations are formed in the following remarkable way. We have seen that the fibre consists of cells which have become detached from the skin, and which have been forced to flic surface. The pressure of the atmosphere upon the cells which have just made their way to the outside causes them tc shrink. The cells which follow form a K’nd of bed for those that have gone bern-c, and in that way protect their lower surface. This process continues contemporaneously with the tbrowing-oil' of cells within the follicle, and the result of tills two-fold operation is the production of the fleece. It may be pointed out that there is one point or serration for every cell which lies on the surface of the fibre.

The wool fibre, as has already been shown, is made up of closely condensed ceils. The action of the atmosphere upon them docs not destroy their individuality, or make it impossible to distinguish between two distinct cells. Though shrunken, every cell remains, and if phi cod under suitable conditions may go back to its original nature. The substance or the cells is .horn-like, and because of this can bo dissolved. These two points should he carefully noted because they have a most important connection with the washing of the wool after it has been shorn, and also upon its felting properl ics.

In a single tranverse section of hair no loss than 1 >OO cells may be seen. Also, when looking at the fibre in this way, three distinct parts are visible.

Owing to the pressure which has been brought to hear upon them, the cells in the outermost layer become elongated, and the second layer contains angular-shaped cells. I he fiat shape of the outer cells is the cause of the prominent undulating lines which appear on the outer surface of the fibre. The central cells which form

the medulla of hair are not .so heavily pressed as toe other cells, and therefore retain their circular shape. By counting a small portion of a cross-

section of hair the number of colls contained therein has been found to he 151*0. If we assume that the average length of each cell is J-looth part of an inch, we find that there arc no less than 000,000 cells in om 1 inch of fibre.

In passing, we may make a few remarks upon the distinction between wool and hair. True wool contains no medulla., and if we were to take a number of fibres, cut them transversely, and place them under the microscope, we should he a hie to distinguish the wool from the fibre hy this means alone. The proper way. ■however, to distinguish between the two kinds of fibre is to note the differences between their outward an pearances. The outer layer of cell; an a hair fibre lies flat upon the inner cells, and thus gives it a smooth appearance; but the scales on the woo! Jibl'c stand out prominently, thus making the surface appeal 1 like the edge df a saw: Points For Growers. Perhaps sonic reader will ask, “IVhat Is the hearing of all this upon the practical side of wool production?” Pastoralists generally are not interested in technical terms and scientific explanations; indeed, they often show a strong dislike for them. Yet the ordinary details of the sheepmaster's life are most closely connected with the technicalities of the wool trade. This is a fact which ought never to be overlooked, and if woolgrowers generally could be bi ought to realise the importance of it, a long stride would be taken towards bringing about a better understanding and-a more amicable feeling'between the man who grows the wool and those who convert it into the finished article. We know that the understanding of which we speak has ■ not yet been arrived at. The woolgrower is too prone to think that Ins interests and the interests of the man who buys his wool are entirely a, variance. The result of this is that little or no interest is taken in toe wool except at shearing time. The interest then shown reveals itself chiefly in a desire to secure the big iest possible price, and to get the wool into the market as quickly as possible if that price appears satisfactory, the price does not please the would-be ...filer, the wool is sometimes foolishly hold over, stored in a room, and kepi until prices sink lower still, or pmhaps until rats and damp have mac.e the wool almost worthless. Surely this is a great mistake. The object of this article is to impress unon wool-growers the importance of their wool, and to take a deeper interest in the same. By so doing they will not only confer a great boon upon manufacturers, but their own interests will be advanced. By studying the way hi which wool grows, by observing the wonderful organism which has been created to promote its growth, ami by remembering the great variety of purposes for whicn the shorn fleeces are used, it will be seen that the subject of wool growing is well worth considering. To wool-growers wo say, study your sheep and study your fleeces. Remember that soil, food, climate and altitude are all important factors which either help or hinder the production of good wool.