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[[start page]]                                           [[page number]] 118
[[underline]] The follow is an exact copy of the Report delivered to the Hon. Board of Longitude, by one of the Gentlemen to whom Mr. Harrison was referred to make a Discovery of the Principles of his Time-Piece.
A Short view of the Improvements made or attempted in Mr. Harrison's Watch. [[/underline]] 

[[Margin]] - Harrison's Defects in common Watches.[[/margin]]

THE Defects in common Watches, which Mr. Harrison proposes to remedy, are chiefly these:
1.  That the Main Spring acts not constantly with the same force upon the Wheels, and through them upon the Ba[[strikethrough]]l[[/strikethrough]]lance.
2.  That the Balance, either urged with an unequal Force, or meeting with a different resistance, from the air, or the oil, or the friction, viberates through a greater or less arch.
3.  That these unequal Vibrations are not performed in equal Times. 
4.  That the Force of the Balance Spring is altered by a change of Heat.

[[Margin]] Remedies proposed and correct[[superscript]]d. in [[underline]] his [[/underline]] Watch. 
Main Spring made to act equally.
Viberations of the Balance made more Uniform[[/Margin]
1. To remedy the first defect, Mr. Harrison has contrived, that his watch shall be moved by avery tender spring, which never unrolls itself more than one-eighth Part of a Turn, and acts upon the Ba[[strikethrough]]l[[/strikethrough]]lance through one wheel only.  But such a Spring cannot keep the watch in Motion a long time.  He has therefore joined another, whose office is to wind up the first spring eight times in every minute, & which is itself wound up but once [[insertion]] in [[/insertion]] a day.
2.  To remedy the second defect, Mr. Harrison uses a much stronger Ba[[strikethrough]]l[[/strikethrough]]lance Spring, than in a common watch.  For if the force of his spring upon the Ba[[strikethrough]]l[[/strikethrough]]lance remains the same, whilst the Force of the other varies, the errors arising from that variation will be the less, as the fixed Force is the greater.  But a stronger Spring will require either a heavier or a larger Balance.  A heavier Balance would have a greater friction.  Mr. Harrison therefore increases the diameter of it.  In a common watch it is under an inch, in this of Mr. Harrison's two inches and two tenths.
[[Margin]]Times of these Vibrations made equal.[[/Margin]]
3.  Had these remedies been perfect, it would have been unnecessary to consider the defects of he third sort.  But the methods already described, only lessening the errors, not removing them, Mr. Harrison uses two ways to make the times of the vibration equal, tho' the arches may be unequal.  One is to place apin, so that the balance Spring, pressing against it, has its force increased; but increased less when the vibrations are larger; the other to give the palates such a shape, that the wheels pressing them with
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