- Software name: appdown
- Software type: Microsoft Framwork
- size: 292MB
In every case where there can be a question as to whether gearing shafts or belts will be the best means of transmitting power, the several conditions named will furnish a solution if they are properly investigated and understood. Speed, noise, or angles may become determinative conditions, and are such in a large number of cases; first cost and loss of power are generally secondary conditions. Applying these tests to cases where belts, shafts, or wheels may be employed, a learner will soon find himself in possession of knowledge to guide him in his own schemes, and enable him to judge of the correctness of examples that come under his notice.
"Something in your line?" Bruce asked.
"I'd exchange for yours any day, and thank you, dear," responded Charlotte; "you're a bunch of sweet-peas. Isn't she, Mr. Smith?""But did she leave any message?" enquired the Doctor, fixing her with his eye-glass.
Inherent or cooling strains in castings is much more intricate than shrinkage: it is, in fact, one of the most uncertain and obscure matters that pattern-makers and moulders have to contend with. Inherent strains may weaken castings, or cause them to break while cooling, or sometimes even after they are finished; and in many kinds of works such strains must be carefully guarded against, both in the preparation of designs and the arrangement of patterns, especially for wheels and pulleys with spokes, and for struts or braces with both ends fixed. The main difficulty resulting from cooling strains, however, is that of castings being warped and sprung; this difficulty is continually present in the foundry and machine-shop, and there is perhaps no problem in the whole range of mechanical manipulation of which there exists more diversity of opinion and practice than of means to prevent the springing of castings. This being the case, an apprentice can hardly hope for much information here. There is no doubt of springing and strains in castings being the result of constant causes that might be fully understood if it were not for the ever-changing conditions which exist in casting, both as to the form of pieces, the temperature and quality of metal, mode of cooling, and so on.But her stare of amazement was quite unaffected. She it was who had locked the front door with the full determination of only opening at her will. But she had not expected to see a figure like this.
"Perhaps you knew also the culprit," the Countess suggested.Breathe, O! breathe to me, as these love-languid skies To yon twilight star breathe, Return, return!