APPENDIX 313 



From the above it will be seen that one degree Centi- 

 grade is equivalent to 9-5 degrees Fahrenheit. Hence 

 the following rules : 



1. To change C. into F. reading, multiply by 9-5 and 

 add 32. 



Example: 50C = (50 X {) + 32 = 112F. 



2. To change F. into C. reading, subtract 32 and 

 multiply by 5-9. 



Example: 182F = (182 - 32) X f =83iC. 



METRIC SYSTEM OF WEIGHTS AND MEASURES. 



This system was devised by the French people and has 

 very extensive application wherever accuracy in weights 

 and measures is desired. Some of its equivalents in 

 ordinary weights and measures are given in the follow- 

 ing table: 



