( 58 ‘ ) 
Refra&ion of the Air, give the Heights greater than 
they a&ually are. But what confirms it flill more, is, 
that according to the Tables above, the Numbers which 
anfwer to the Heights of the Mercury, as they were 
obferved at the Top of fome of thpfe Mountains, are 
confiderably lefs, and that even Monf. CajJinis own 
Numbers, which yet we have by fome undoubted Ex- 
periments (hewn to be too great, fall often fhort. It 
will be enough to mention two or three Inflances. At 
the Tower of Maffane in RouJJillonjhe Mercury flood 
at and the Height of that Place was deter- 
mined trigonometrically, of - 397 Toifes. 
Now 25'' 5 /// anfwer according?' 
Mariotte , to - - ^ 34 1 0 
According to CaJJini , - - 392 4 
According to Dr. Scheuchzer - - 350 o 
^ 4 J - ft £ Si j ' ' J ‘ * ( - % ’ • , . [ | ^ j i l j T 
At the Top of the Mountain called la Cofie in Au- 
vergne, the Mercury flood, 061 . 9, 1700, at 23"' ^ fr y 
and the Height of this Mountain was determined Tri- 
gonometrically of 
Now 23 " 4 r// anfwer ac- 
- 851° Toifes. 
cording to Mariotte £0 
Cafjini 
Dr. Sbeuchzer 
The Difference is flill more' 
confiderable withRegardto 
the high Mountain Mont A' 
or enAuvergnejtheYleig 
whereof was determi: 
ed Trigonometrically to 
1040 Toifes. . 
At 
