APPENDIX. 



A. USEFUL RULES AND TESTS. 



Comparison of Thermometer Scales. 



Centigrade Scale — Freezing point of water = 

 Boiling point of water = 100 



Difference 100 degrees. 

 Fahrenheit Scale — Freezing point of water = 32 

 Boiling point of water = 212 



Difference 180 degrees. 

 100 degrees C. = 180 degrees F. 

 5 " = 9 " 



To Change Degrees Centigrade to Equivalent Degrees 

 Fahrenheit. 



Multiply by f and add 32 ; e. g. : 65° C. X f = 117 + 32 

 149° F. 



To Change Degrees Fahrenheit to Equivalent Degrees 

 Centigrade. 



Subtract 32 and multiply by f ; e. g. : 98° F. — 32 = 6G X f 

 = 37°— C. 



To Find the Specific Gravity by the " Board of Health " 

 Lactometer. 



Multiply the reading by .29 and add 1.000 ; e. g.: Observed reading, 

 94 X .29 = 27.26 + 1.000 = 1.027.4- specific gravity. 



(259) 



