An attempt toward obtaining invariable measures of length, capacity, and weight, from the mensuration of time / [John Whitehurst].

  • John Whitehurst
Date:
1792?]
Catalogue details

Licence: Public Domain Mark

Credit: An attempt toward obtaining invariable measures of length, capacity, and weight, from the mensuration of time / [John Whitehurst]. Source: Wellcome Collection.

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    [ * ] Firft, it is propofed to obtain a meafure of the greateft length conveniency will permit, from the menfuration of time, with eafe and certainty; pre- fuming that a meafure of confiderable length may be fubdivided with a much greater degree of accuracy, than a fhort one can be multiplied into a longer. Secondly, it is propofed to obtain the meafure from two pendulums, whofe vibrations are to each other as two to one, and whofe lengths coincide with the Engliftiftandard in whole numbers, either feet or inches; in order to Amplify the operations depending upon them, and alfo with a view of eflablifhing the Britifti meafures upon a natural permanent foundation, which may enable all future generations to obtain fimilar meafures with eafe and certainty. Such are the objedls to be obtained by the con- ftruction of the apparatus. According to the dodlrine of pendulums, the number of vibrations performed in a given time, are inverfely as the fquare roots of their refpediive lengths; and yet we And but few infiances wherein the lengths of pendulums coinciding with Englifh mea- fure. V