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In the mill where I found the friction 39 per cent. the shafting was rather heavy, but not extremely so. I attributed the excessive friction here to the multiplicity of bearings, and all of a very bad construction, the boxes being absolutely rigid. Of course the difference between 39 per cent. and 22 per cent. is worth saving. It would represent 170 horse-power on a mill requiring 1,000 horse-power, and this would represent a needless loss of $1,700 a year for fuel alone, in the best steam mill. And, more than this, in some cases of partly water and partly steam power mills it may mean the still larger losses from stoppage of machinery or loss of speed, which might be overcome merely by reducing the friction down to a reasonable point. This was, in fact, exactly the case in the mill in question, which I tested recently on account of this condition of things.

High speed of shafting in carding and weaving rooms is especially to be avoided. I have in mind a large mill in which the shafting in these rooms runs over 320 revolutions. The loom pulleys are 5 to 6 inches diameter, the belts very tight; of course the shafting is very small, with bearings every 5 feet, and in one room with 384 looms there are over 500 bearings, whereas half that number with a proper arrangement would have sufficed. Every one of these 250 unnecessary bearings means more or less unnecessary friction.

In yarn mills the friction is of course less than in weaving mills. I have found it about 18 to 19 per cent.

The suggestion that has been made by electricians to overcome this waste of power in friction by attaching motors to each line will evidently not accomplish the purpose. The shafting and machine belts will still remain, besides having the loss from the conversion of power, - about 15 per cent. in the present state of the art.

Carrying steam to a number of small engines distributed about the mill was once suggested, I believe, in a certain mill, but of course is not to be thought of. At present the only thing to do is to avoid extreme speed, use bearings of good

construction and in as small number as possible, and by a good arrangement keep the friction down to as low a point as possible.

Although in this paper I have emphasized the supreme importance of high speed of spindles and the reliability of the motive power, rather than a fine economy of fuel, yet it of course goes without saying that this economy is to be sought also by every practicable method; and all improvements in steam engineering to this end are to be welcomed, so long as they do not raise any question as to the more vital point in cotton manufacturing, certainty of continuous operation.

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construction and in as small number as possible, and by a good arrangement keep the friction down to as low a point as possible.

Although in this paper I have emphasized the supreme importance of high speed of spindles and the reliability of the motive power, rather than a fine economy of fuel, yet it of course goes without saying that this economy is to be sought also by every practicable method; and all improvements in steam engineering to this end are to be welcomed, so long as they do not raise any question as to the more vital point in cotton manufacturing, certainty of continuous operation.

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