Gill's technological [afterw.] Gill's scientific, technological & microscopic repository; or, Discoveries and improvements in the useful arts, a continuation of his Technical repository, by T. Gill, Volumen6 |
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Página 48
... thickness and elevation of the walls ; and also the length of time during which crude bricks must be allowed to dry . At Utica this was extended to five years , a less period not being accounted sufficient to ensure that perfect ...
... thickness and elevation of the walls ; and also the length of time during which crude bricks must be allowed to dry . At Utica this was extended to five years , a less period not being accounted sufficient to ensure that perfect ...
Página 50
... thickness of nearly a foot . The proportions of the ingre- dients used , are about fourteen parts of lime in a pasty state , ninety parts of the unequal grained sand , and twenty of the pebbles . These prisms commonly lie buried for ...
... thickness of nearly a foot . The proportions of the ingre- dients used , are about fourteen parts of lime in a pasty state , ninety parts of the unequal grained sand , and twenty of the pebbles . These prisms commonly lie buried for ...
Página 67
... thickness . In plate II . fig . 1 re- presents one of these portions , as being surrounded with a little water , when placed upon a slip of glass , and ready for examination under the microscope . fig . 2 is a magni- fied view of part ...
... thickness . In plate II . fig . 1 re- presents one of these portions , as being surrounded with a little water , when placed upon a slip of glass , and ready for examination under the microscope . fig . 2 is a magni- fied view of part ...
Página 96
... thickness , so it became exceed- ingly difficult to form them . And , in fact , it was only accomplished by raising them by degrees out of plates of cast - steel , frequently annealed , in sets of dies made on pur- pose , and which ...
... thickness , so it became exceed- ingly difficult to form them . And , in fact , it was only accomplished by raising them by degrees out of plates of cast - steel , frequently annealed , in sets of dies made on pur- pose , and which ...
Página 100
... thick or thin , should be rather porous , or what is called half - sized paper . Then , with a flat camel's hair brush , first lay a coat of common parchment size upon the paper , and let it dry in ; then lay on the above paste , in the ...
... thick or thin , should be rather porous , or what is called half - sized paper . Then , with a flat camel's hair brush , first lay a coat of common parchment size upon the paper , and let it dry in ; then lay on the above paste , in the ...
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Pasajes populares
Página 268 - I have seen a small manufactory of this kind where ten men only were employed, and where some of them consequently performed two or three distinct operations. But though they were very poor, and therefore but indifferently accommodated with the necessary machinery, they could, when they exerted themselves, make among them about twelve pounds of pins in a day.
Página 75 - These are thy glorious works, Parent of good, Almighty, thine this universal frame, Thus wondrous fair; thyself how wondrous then ! Unspeakable, who sitt'st above these heavens, To us invisible, or dimly seen In these thy lowest works; yet these declare Thy goodness beyond thought, and power divine.
Página 269 - But if they had all wrought separately and independently and without any of them having been educated to this peculiar business, they certainly could not each of them have made twenty, perhaps not one pin in a day...
Página 268 - One man draws out the wire; another straights it; a third cuts it; a fourth points it; a fifth grinds it at the top for receiving the head...
Página 272 - Every workman has a great quantity of his own work to dispose of beyond what he himself has occasion for ; and every other workman being exactly in the same situation, he is enabled to exchange a great quantity of his own goods for a great quantity, or, what 'comes to the same thing, for the price of a great quantity of theirs. He supplies them abundantly with what they have occasion for, and they accommodate him as amply with what he has occasion for, and a general plenty diffuses itself through...
Página 273 - ... is requisite in order to form that very simple machine, the shears with which the shepherd clips the wool. The miner, the builder of the furnace for smelting the ore, the...
Página 273 - The shepherd, the sorter of the wool, the wool-comber or carder, the dyer, the scribbler, the spinner, the weaver, the fuller, the dresser, with many others, must all join their different arts in order to complete even this homely production.
Página 266 - But this proportion must in every nation be regulated by two different circumstances : first, by the skill, dexterity, and judgment with which its labour is generally applied ; and, secondly, by the proportion between the number of those who are employed in useful labour, and that of those who are not so employed.
Página 269 - The great increase in the quantity of work, which, in consequence of the division of labour, the same number of people are capable of performing, is owing to three different circumstances: first, to the increase of dexterity in every particular workman; secondly, to the saving of time, which is commonly lost in passing from one species of work to another; and, lastly, to the invention of a great number of machines which facilitate and abridge labour, and enable one man to do the work of many.
Página 270 - A man commonly saunters a little in turning his hand from one sort of employment to another. When he first begins the new work, he is seldom very keen and hearty; his mind, as they say, does not go to it, and for some time he rather trifles than applies to good purpose.