THERMOMETERS 



527 



Whole Days at — 



Thermometer Scales 



Fahrenheit. — The fref3zing-point is taken as the thirty-second degree 

 of the scale, and 180 degrees are made between that and the boiling- 

 point, which therefore becomes 212^. The zero of Fahrenheit was sup- 

 posed to represent the absolute zero, or lowest po.ssible temperature. 



Centigrade or Celsius. — The freezing-point of water Is taken as zero, 

 and boiling-point as 100^. 



Reaumur. — The freezing-point of water is taken as zero, the boiling- 

 point as 80°. A degree Centigrade Is therefore greater than a degree of 

 Fahrenheit as 9 Ls greater than 5; and a degree of Reaumur Is greater, 

 as 9 Is greater than 4. 



To reduce Fahrenheit degrees to Centigrade, subtract 32 from the 

 given degree of Fahrenheit, and multiply the remainder by 5 and 

 divide it by 9 ; CF. degrees — 32) f- To reduce Centigrade to Fahr- 

 enheit, multiply the given degree of Centigrade by 9 and divide the 

 product by 5, then to the quotient add 32: (f C.° + 32). 



To reduce Fahrenheit to Reaumur, subtract 32 from the given 

 degree of Fahrenheit and multiply the remainder by 4 and divide 

 by 9 : fF.°-32)i 



To reduce Reaumur to Fahrenheit, multiply the given degree of Reau- 

 mur by 9 and divide by 4, then add 32 : (I R° + 32). 



To reduce Reaumur to Centigrade, multiply by f . 



