634 Sir g . shuckburgh’s Letter to Col. roy on 
iViean 
heat. 
Mean’ height of the two barometers in inches. 
O 
0 
3 ° 
29 
28 
27 
26 
25 
24 
23 
22 
21 
20 
3 2 
0 
0 
0 
0 
O 
0 
0 
0 
0 
0 
O' 
42 
0 
— I 
— 2 
- 3 
- 4 
~ 5 
- 6 
- 7 
- 8 
- 9 
52 
4-2 
0 
— 2 
-4 
- 6 
- 8 
— 10 
— 12 
- x 4 
~i6 
— *7 
62 
4-5 
4-2 
— I 
-4 
- 7 
— 10 
-*3 
-16 
-*9 
— 22 
-25 
72 
4-3 i 
4-4 
0 
-4 
— 10 
— 12 
-17 
— 21 
-25 
-29 
-33 
Thus, if the mean height of the barometer were 27 
inches, and the temperature 5 2 0 , the difference of the 
refults would be four feet in a thoufand; how far, there* 
fore, this is of moment is left to the judgement of the 
obferver. I conclude laftly, sir, with a comparifon of 
your aftual obfervations made in Great Britain computed 
after my tables, deduced from a feries of obfervations 
made in Savoy. I have indeed only collected fixteen of 
your obfervations ; but as I have chofen fuch as prefented 
themfelves as molf proper, either on account of their 
heights or temperatures, I imagine thefe will be very 
fatisfadlory. 
Place 
