Viewing page 331 of 504

This transcription has been completed. Contact us with corrections.

[[right corner]] (140 [[/right corner]][[left margin][ Great Cold & Snow there.
[[/left margin]]
[Body]
very severe, there being frost at different times, from the 15. [[superscript]] th [[/superscript]] day of September, to the 21. [[superscript]] st [[/superscript]] day of June following, on which day I broke a thin skin of ice on a pond and on the 31. [[superscript]] st [[/superscript]] day of May measur'd a bank of Snow which lay near the sea, eleven feet perpendicular height, and half a mile in length. We had two continued frosts night and day, the lasted from the 14. [[superscript]] th [[/superscript]] day of November to the 6. [[superscript]] th [[/superscript]] day of January; and the other from the 12. [[superscript]] th [[/superscript]] of the same month, to the 23. [[superscript]] d [[/superscript]] day of March following; during each of these set frosts, the thermometer was from ten, twenty, thirty, to forty seven degrees below the freezing mark, and the sea seldom to be seen for the quantity of ice & Snow which was spread over its surface."

[[left margin]] Expansions of Metals v. p.92. and 155-7 also p.4. [[/left margin]]


In the [[underline]] hist. of the Royal Acad. of Sciences at Paris [[/underline]], for 1703, from a very accurate experiment by [[underline]] M. de la Hire [[/underline]], it appears, that a bar of iron 6 feet long, [[insertion]] when [[/insertion]] exposed to the frost in winter, gained or expanded 2/3 of a line, when exposed to the heat of the sun in summer.
And in the same memoir he says, M. [[underline]] Picard [[/underline]] having exposed bodies to the frost, and putting [[insertion]] them [[/insertion]] afterwards near the fire, observed a prolongation of 1/4 of a line, in the length of a foot; which gives 3/4 of a line in the length of a pendulum: but he found only 1/3 of a line, in exposing the bodies to the sun the following summer. 

[left margin] The uncertainty of measuring this expansion, & a universal standard measure proposed. Largely treated of in Dr. Hooke's Posthumous Works p. 458. & p. 472 [[/left margin]]

He goes on & shews the uncertainty of measuring this expansion, from the standard measure suffering the same effect: for an iron rod of 3 feet at [[underline]] Paris [[/underline]] was prolonged 5/4 of a line at [[underline]] Cayenne [[/underline]], where the length of a pendulum beating seconds [[strikethrough]] ???[[/strikethrough]] measured there with this rod, would be found shorter than at Paris by 5/4 of a line, tho' in reality it was the same in both places. So at [[underline]] GoreƩ [[/underline]] this rod or measure was prolonged 2 lines more than at [[underline]] Paris [[/underline]]; the length of the pendulum beating seconds, measured with this rod, must therefore appear shorter than at [[underline]] Paris [[/underline]] by 2 lines. "If it was so, the universal measure of the "pendulum would remain always the same, over all the earth,"and the particular measure should be regulated by this measure, "taking the length of the simple pendulum for 3 feet, or 1/2 a toise."
      Martyn's & Chamber's abridgement, Vol.2. p. 110, & 111.  The same is proposed in Question 205. page 875. of Martin's Magazine Vol 2. for the year 1758. by R. Waddington of Hull. who in the Jan [[superscript]] y [[/superscript]] & Mag. following answers it thus 

    By the [[underline]] Newtonian [[/underline]] philosophical principles of the mathematics, I find the length of pendulums vibrating seconds in the Latitudes as follows, [[underline]] viz. [[/underline]]

[[table-3 columns after each location Latitude, Length of Pend. Inches French., Length of Pend. Inches English.]]
Paris, at the observatory  48.50 --- 36,7134 --- 39,161 
[[Second line for Paris]] 50 --- 36,7161 --- 39,164
[[Third line for Paris]] 51 --- 36,7188 --- 39,167
London, the Tower________ 51..32 ---36,72 --- 39,168
[[Second line for London]] 52 --- 36,7215 [[this number bracketed with next line in column]] --- 39,170
Cambridge --- 52..17 --- 36, 7215 --- [[bracketed with number above]] 39,170
[Second line for Cambridge] 53 ---36,7242 --- 39,173
York, at the Castle ---- 54. ---- 36,727 --- 39,176
[[Second line for York]] 55. ---36,7297 --- 39,178
Edingburgh, Scotland --- 55..57 ---  36,732 --- 39,180
[[End Table]]

   The Latitude of the place being known, and having a good pendulum clock adjusted to vibrate seconds in a temperate air, the center of

Transcription Notes:
"If it was so ..." - This line has quotes at the beginning of each line, though I suspect it represents one quotation.