6. The diminished cost of generating power on a large scale, compared with a number of separate steam engines distributed over manufacturing districts.First. By combining two or more operations in one machine, the only objects gained are a slight saving in first cost, one frame answering for two or more machines, and a saving of floor room. :+375 17 299-50-70 +375 17 245-99-81
"But I have only one disguise in the house--the old one."
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Mamie was thirsty. She scornfully refused a suggestion of soda-water; nothing would content her but a certain fruit salt that came from a certain place some way off. She was quite sure that she could not do without it, and that unless the salt was forthcoming she would have a dreadful headache in the morning.Considered upon grounds of commercial expediency as a question of cost alone, it is generally cheaper to move material by hand when it can be easily lifted or moved by workmen, when the movement is mainly in a horizontal direction, and when the labour can be constantly employed; or, to assume a general rule which in practice amounts to much the same thing, vertical lifting should be done by motive power, and horizontal movement for short distances performed by hand. There is nothing more unnatural than for men to carry loads up stairs or ladders; the effort expended in such cases is one-half or more devoted to raising the weight of the body, which is not utilised in the descent, and it is always better to employ winding or other mechanism for raising weights, even when it is to be operated by manual labour. Speaking of this matter of carrying loads upward, I am reminded of the fact that builders in England and America, especially in the latter country, often have material carried up ladders, while in some of the older European countries, where there is but little pretension to scientific manipulation, bricks are usually tossed from one man to another standing on ladders at a distance of ten to fifteen feet apart.
To construe the term "transmission of power" in its full sense, it will, when applied to machinery, include nearly all that has motion; for with the exception of the last movers, or where power passes off and is expended upon work that is performed, all machinery of whatever kind may be called machinery of transmission. Custom has, however, confined the use of the term to such devices as are employed to convey power from one place to another, without including organised machines through which power is directly applied to the performance of work. Power is transmitted by means of shafts, belts, friction wheels, gearing, and in some cases by water or air, as various conditions of the work to be performed may require. Sometimes such machinery is employed as the conditions do not require, because there is, perhaps, nothing of equal importance connected with mechanical engineering of which there exists a greater diversity of opinion, or in which there is a greater diversity of practice, than in devices for transmitting power.
CHAPTER XXXII. SLOTTING MACHINES. . , , , , , , .
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