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meeting, the same subject will be again introduced, and by invitation, Rev. E. C. BOLLES, D. D., of the Essex Institute, will present results of his microscopic and other investigations of the cotton fibre, made under the auspices of the Association, illustrating his statements by an exhibition of fibres on an enlarged scale by means of the solar microscope.

[The President also exhibited to the meeting a specimen of a bleachery-eye of rubber made by the Boston Belting Company, and also a squeeze-roll, both of which were laid on the table for the inspection of the members.]

The preparations for conducting the experiments illustrative of Dr. Bolles's lecture having been completed, the Association adjourned to the lecture-room, which was darkened and otherwise fitted up for the purpose of exhibiting the microscopic experiments, and a great number of experiments were given during the progress of the address.

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Gentlemen of the Association :

I naturally feel a great deal of embarrassment in addressing an assembly of practical men like those I see before me, especially upon a question towards which so much of experiment and scientific investigation has been directed. I feel that it is almost impossible for one who is purely a man of theory, at least so far as regards cotton manufacturing, to answer all the questions which will naturally arise in your minds regarding this subject, or to make every portion, perhaps, of my own views clear to you. Permit me to begin at the very beginning.

You may look at a cotton fibre in different ways. Botanically, it is the hair on the seed of a plant,-a development which I suppose it is in the plant's nature to put there for the purpose of shielding the infant germ of the seed. At first it is a cylindrical, tapering body. In fact, it is a vegetable cell, as all hairs are; with this exception, that while many hairs are built up of a series of cells placed end to end, the cotton fibre is a single cell,

—that is, in its green condition, when the life of the plant is still pushing it forward to other developments. But in the ripe cotton fibre, changes have occurred in this hair by drying. The cotton fibre shrinks; it flattens, bringing the two faces together in the centre. It leaves it, of course, in the shape of a ribbon, where the edges are thicker than the middle, and where there is a pear-shaped air-space also running the whole length of the fibre on each side, with its blunt end outward. That is not all. The material of which the cotton hair is composed is such, that, in shrinking and drying, it also twists. You may notice the same phenomenon in a great many vegetable substances. There are certain mosses, for instance, that when they dry have their stems twisted, and there are some that have received their specific botanical names from this circumstance

in their history. That is what the cotton fibre is, botanically speaking

Chemically speaking, the cotton fibre is cellulose of a very pure description. It is to the cotton fibre that we go for the purest specimens of this substance. It may be said to be composed of the elements, carbon and water. They are combined in the cotton fibre in the same atomic weights that they are in starch, although they have a different molecular arrangement. This substance is remarkable for a number of qualities. In the first place, it resists the effect of chemical action very effectually; it resists the action of water; it resists the ordinary operations of decay. Under favorable conditions, it is a very permanent thing. Here are cotton fibres which were spun and woven into cloth by the old Peruvians thousands of years ago, and which still envelop the mummies of that ancient people, and are just as perfect as when originally devoted to that use, although a little browned with age.

Cellulose, while it is capable of a number of very curious transformations, is a very tough substance, and will bear, especially when dampened, a large amount of mechanical action without suffering injury; and on this account, I suppose, it is

I that you employ a certain amount of moisture in working the fibre. It becomes too brittle, and breaks if too dry; but being allowed to take up its proportion of water at this stage of its preparation, it comes into the most favorable condition for being worked upon. This condition also confirms the the which we shall state regarding the cotton fibre in the processes of manufacture.

You will see, then, that there are two things which may affect the value of a cotton fibre. In the first place, the absolute size and relative proportions of the parts. In order to get at the true cure for all the evils in cotton-spinning, one must be able to command the elements. Having provided a soil and climate just right for growing the cotton-plant, he must also have a season that is perfect; for you see that the weight and strength of the cotton fibre depend not only on the arrangement of its particles in that shape, which I told you was cylindrical, and becomes a flattened ribbon after being dried, but also upon the absolute amount of this cellulose of which it is made up. But this, of course, depends upon the amount of nourishment which the plant receives; and it is probable, too, that it is in consequence of some fibres being substantially thicker than others, that those fibres undergo a greater amount of twist when they are dried than others do. Hence all the phenomena with which you are familiar, of heavily twisted fibres, thick and thin fibres, abortive and stunted fibres, and the like, are accounted for. When you would produce the best cotton fibre, you must provide good soil, good seed, and the best possible climate. Then you will have cotton in the boll as nearly perfect for the purposes of working as you can have it. I think that a great deal of the difficulty you fiud in the working of cotton, a great many things which call out your ingenuity and stimulate your competition, are due to differences from year to year and from bale to bale; for cotton, though it may be raised from the same seed, and apparently to the outside eye may be the same thing in the market, may be quite a different thing when submitted to a scientific examination.

I go on a step beyond this, to ask what there is in the process of manufacture that may serve to injure a fibre so built up and so constructed. Let me analyze, if you please, the possible causes that may come in to hurt the cotton fibre as it is being manufactured. In the first place, there is an absolute mechanical injury in splitting, or crushing, or breaking the fibres, which machinery, and especially ill-regulated machinery, will be sure to do; but so far as I have been able to examine different samples of cotton, following it in a great number of instances from the boll to the finished yarn, it seems to me that this kind of mechanical injury to cotton is much less than bas sometimes been supposed. It seems to me that in almost any well-regulated mill, where the ordinary processes of spinning are carried forward properly,—where rolls are properly covered and the various departments of the drawing process carefully regulated,-a much less percentage of broken, displaced, and distorted fibres occur, than may have been conceived. It seems to me that in regard to this there is a misapprehension ; at any rate, I have not been enabled by the examination of thousands of specimens to find the number of broken, cracked, torn, and jagged fibres that I was prepared to meet, and that injury to the edge of the fibre of which something has been said ; and I

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think I can show you on the screen that it is practicable, in

any fair working of cotton, to reduce this injury almost to a zero.

A delicate cotton fibre, one thousandth of an inch in diameter, is hardly affected in any of the ordinary processes of drawing so as to make the edge of the fibre saw-like. If it is, it must be done in this way: by the overlapping of the edges and the grinding of one fibre upon the other. Now, it is the work of all machinery which precedes the drawing-frame to get cotton fibres parallel with each other, so that any amount of compression or lateral twist will act upon them in the least favorable position for injury, since they are most subject to injury when crossed in all directions upon each other.

The second sort of injury which it appears to me may come to the cotton fibre, is that of disturbance of the proportion of twist, or the number of turns to the inch, or fraction of the inch, which the cotton fibre may possess, and which are evidently one reason why cotton can be so successfully spun. If you will look at it a moment, you will see that if you take, for instance, a number of rods placed parallel to each other, on bringing them gradually into contact and filling up the interstices with any number of others, that their adhesion and resistance to a draught in the direction of their ļength will be in proportion to the pressure by which the surfaces are made to adhere to each other, and the irregularities of the surfaces which may interlock one with the other and make the compound bundle strong in the direction of its length. Now, if you take the cotton fibre, which is not a perfect cylinder, but which is a flattened and twisted ribbon, and arrange any number of such fibres one upon the other, and then apply pressure, it is manifest that you will have not only the adhesion of one fibre upon the other, but also the interlocking of these twists or turns, or corkscrew shapes which the fibres themselves possess. If, in addition to that, you give the entire mass of fibres a twist, supposing them not to lie with their ends on the same point in the mass of cotton fibre, but as they actually do in the drawing process, overlapping and interlacing in the way which I now illustrate,-if you give such a bundle of fibres a twist, it is evident that the strength of the thread or yarn, measuring it by the pull which is necessary in order to separate it, will be much greater if these fibres are thoroughly twisted ; and, of course, anything

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