INTRODUCTION. 



DESCRIPTION AND USE OF THE TABLES. 



THERMOMETRICAL TABLES. 



COMPARISON OF THERMOMETRIC SCALES. 

 Conversion of readings of the Reaumur thermometer to readings _,„. ^ , 



•' o J TABLE 1 . 



of the Fahrenheit a?id Centigrade thermometers. 



The argument is given for every Reaumur degree from + 80° to — 40° 

 Reaumur, and the corresponding readings Fahrenheit and Centigrade are 

 given to hundredths of a degree, permitting the exact values to be 

 expressed. A column of proportional parts gives the values corresponding 

 to tenths of a Reaumur degree. By the help of the column of proportional 

 parts, the table is also conveniently used for converting Fahrenheit to 

 Centigrade and Reaumur, and Centigrade to Fahrenheit and Reaumur 

 throughout the thermometric scale from the boiling point of water to 

 -60° F. or -51° C. 



The formulse expressing the relation between the different scales are 

 given at the bottom of the table, where 



F° — Temperature Fahrenheit. 

 C° = Temperature Centigrade. 



R° — Temperature Reaumur. 

 Examples : 



To convert 18:3 Reaumur to Fahrenheit and Centigrade. 



From the table, iSro R. = 72^50 F. = 22^50 C. 



From column Prop. Parts, 0.3 = 0.675 = 0.375 



i8r3 R. = 73-2 ^- = 22:9 C. 

 To convert i47°7 Fahrenheit to Centigrade and Reaumur. 



From the table, 146:75 F. == 63-75 C = 5i-0^- 



From column Prop. Parts, 0.95 = 0.53 = 0.4 



I47f7 F. = 64f3 C. = 5i-4^- 



To convert 16:9 Centigrade to Fahrenheit and Reaumur. 



From the table, 16^256:= 61^25 F. = 13:0 R. 



From column Prop. Parts, 0.65 = 1.17 = o-5 



16^9 C = 62^4 F. = 13-5 ^• 

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