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[[left-hand margin]] Talbot's Micrometer considered. An inconveniency therein, remov'd. [[/left-hand margin]]

This index i shewing the seconds upon the plate A B under it, and driving another wheel for minutes or No. of its revolutions, gains a great space from the bottom A & thereby admitting the circle upon the plate for seconds of a considerable Radius; whereas Talbot's method of shewing seconds by the index at a [[i.e. point a]] must be from a circle of a small diameter upon the plate, because the screw ab must be so near the Edge A A as to be out of the field of view.

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