iSi 



Experiments to a/certain 



Trial I ft. 



Divifion on the 



micrometer. 



63 



66 

 70 

 66 



therm. 



Mean = 



66 



Trial id. 



Divifion on the 



ipicrometer. 



64 

 62 



6S 



63 

 624 



therm. 

 '62^0 



63,3* 



Trial 3<3- 



Divifion on the 



micrometer. 



64 r 

 65 



66 

 63 



64,2 



therm, 

 62S3 



The mean of thefe three means is 64,5 with the temperature 62",!. 



(§. 27.) The bar was now removed from the gauge, and the fphere put there in its place j 

 and, by means of the three great circles, each of which was divided into 8 equal parts, nin? 

 feveral diameters of the fphere were taken, as follow : 



diam. 

 AB 



Div. of 



microm. 



diam. 

 GH 



the 



40 



\, i LllCIl 

 .44J 



5 



42,6 • 



The above four mean dimenfions may be called equatarial, viz. 



therm. 

 62^,5 



The mean of which is 



Div. of micr. 



■44' 



diam. 

 EF 



46 



44 



45 



L45. 



therm.. 

 62%5 



Mean 44,8 



Div. of micr. 

 . f42-l 

 diam. J ^^ ! therm. 



.41J 





42,6 



diam. 

 3.4- 



Thefe three laft dimenfions, together V(^ith the ift of the preceding fet, may be_^ 

 called meridional., being in a circle a« right angles to the former, viz. 



The mean of which is - 



■and differs from the former not quite Toioo inch.^ 





= 43.S 



* In all thefe experiments with the gauge, the figures on the micrometer plate increafe as the fcrew goes 

 Jotward; viz. the higher numbers indicate a lefs interval or diameter. 



Ih 



