File:A new and complete dictionary of trade and commerce - containing a distinct explanation of the general principles of commerce; an accurate definition of its terms a particular description of the (14762804312).jpg

Identifier: newcompletedicti02mort (find matches)
Title: A new and complete dictionary of trade and commerce : containing a distinct explanation of the general principles of commerce; an accurate definition of its terms ... a particular description of the different productions of art and nature, which are the basis and support of commerce ... foreign commerce ...
Year: 1766 (1760s)
Authors: Mortimer, Thomas, 1730-1810 Adams, John, 1735-1826, former owner. BRL Boston Public Library) John Adams Library BRL
Subjects: Commerce Industries Commercial law
Publisher: London : Printed for the author and sold by S. Crowder ...
Contributing Library: John Adams Library at the Boston Public Library
Digitizing Sponsor: Internet Archive

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nate in an angle,greater or lefs, according to the fkill, or fancy, of theworkman. Thefe needles, though infinitely preferable tothe other, are, however, far from being perfeft; for everyneedle of this form hath fix poles inftead of two, one ateach end, two where it becomes tapering, and two at thehole in the middle; this is owing to their fhape, for, themiddle part being very flender, it has not fubftance enoughto conduft the magnetic ftream quite through from oneend to the other : all thefe poles appear very diftinftly,when examined with a glafs that is fprinkled over withmagnetic fand. This circumftance, however, does nothinder the needle from pointing true; but as it has lefsforce to move the card than when the magnetic ftreammoves in large curves, from one end to the other, it iscertainly an imperfection. A needle that is quite ftrait, and fquare at the ends, has been found to have only two poles, but, about the hole in the middle, the curves are a little confufed. Thefe, 4 after
Text Appearing After Image:
N E G N E G after vibrating a long time, will always point exactly inthe fame direction; and, if drawn never fo little on onefide, will return to it again, without any fenfible diffe-rence. We may, therefore, conclude, that a regular pa-rallelopiped is the beft form for a needle, as well as thefimpleft, the holes for the caps being as fmall as poffible. And as the weight fhould be removed to the greateft di-ftance from the center of motion, a circle of brafs, of thefame diameter of the card, may be added, which will fervealfo to fupport the card, which may then be made of thinpaper, without any thing to ftiffen it. This ring beingfixed below the card, and the needle above it, the centerof gravity is placed low enough to admit of the cap beingput under the needle, whereby the hole in the needle be-comes unneceffary. NEEDLE-MAKER. The boy intended to be put ap-prentice to this bufinefs, does not require much ftrength orlearning; but he ought to have good eyes, a pretty lighthand, and a

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