MANUFACTURES.

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I. Mann- Another instrument for registering is used in some establishments for calendering Sect 1

and embossing. Many hundred thousand yards of calicoes and stuffs pass weeklythrough these operations, and as the amount paid for the process is small, the timespent in measuring them would bear a considerable proportion to the profit. A Machinehas been contrived for measuring and registering the length of the goods as they passrapidly through the hands of the operator, and all chance of erroneous counting is thusavoided.

Perhaps the most useful contrivance of this kind, is one for ascertaining the vigi- Teii-uie.lance of a watchman. It is a piece of Mechanism connected with a clock placed in anapartment to which the watchman has not access; but he is ordered to pull a stringsituated in a certain part of his round once in every hour. The instrument, aptlycalled a tell-tale, informs the owner whether the man has missed any, and what, hoursduring the night.

X. ECONOMY OF THE MATERIALS EMPLOYED.

The precision with which all operations by Machinery are executed, and the exactsimilarity of the articles thus made, produce a degree of economy in the consumptionof the raw material which is in some cases of great importance.

The earliest mode of cutting the trunk of a tree into planks, was by the use of thehatchet or the adze. It might, perhaps, be first split into three or four portions, andthen each portion was reduced to a uniform surface by those instruments. With suchmeans the quantity of plank produced would probably not equal the quantity of the rawmaterial wasted by the process, and, if the planks were thin, would certainly fall far shortof it. An improved Tool, the saw, completely reverses the case: in converting a treeinto thick planks it causes a waste of a very small fractional part; and even in reducingit to planks of only an inch in thickness, it does not waste more than an eighth part ofthe raw material.

The rapid improvements which have taken place in the Printing Press during the lasttwenty years, afford another instance of saving in the materials consumed, which isinteresting from its connection with Literature , and valuable because admitted and wellascertained by measurement.

In the old method of inking type, by large hemispherical balls stuffed and coveredwith leather, the printer, after taking a small portion of ink from the ink-block, was con-tinually rolling them in various directions against each other, in order that a thin layerof ink might be uniformly spread over their surface. This he again transferred to thetype by a kind of rolling action. In such a process, even admitting considerable skill inthe operator, it could not fail to happen that a large quantity of ink should get near theedges of the balls, which, not being transferred to the type, became hard and useless,and was taken off in the form of a thick black crust. Another inconvenience alsoarose, the quantity of ink spread on the block not being regulated by measure, and thenumber and direction of the transits of the inking balls over each other depending on

Mode ofspreadingink on type.

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