18 Introduction. 



it is desired to remove the animal odors this if possible 

 should be done first and then the milk cooled to prevent 

 the formation of other odors. 



20. Work. Whenever any body is moved under the ac- 

 tion of a force work is done and the amount of this work 

 is measured by the intensity of the force and the distance 

 through which it has acted. When a body weighing one 

 pound is lifted one foot against the attraction of the earth 

 the amount of work done is one foot-pound. The same 

 weight lifted 10 feet represents 10 foot-pounds and 10 

 pounds raised one foot has the same value. 



A team hauling a load over a road under a mean pull 

 of 200 pounds is doing 200 foot-pounds of effective work 

 for every foot traveled and in traveling 10 miles the total 

 work done is 



10 X 5, 280 X 200 = 10, 560, 000 foot-pounds. 



When a larger unit than the foot-pound is desired that of 

 the foot-ton may be employed and its value is 2,000 pounds 

 lifted one foot high or 2,000 foot-pounds. If a wagon 

 with its load weighing 4,000 pounds is moved along the 

 road the work done will not be measured by the product 

 of the load into the distance traveled but by the intensity 

 of the pull necessary to pull the load into the distance trav- 

 eled. On a good level macadam road 60 pounds will move 

 a ton and 120 pounds two tons. To draw four tons over 

 10 miles of such level road means the doing of 



So, too, if the pressure of steam on the head of the piston 

 in a steam engine is 80 pounds per square inch and the 

 area of the piston is. 100 square inches the amount of work 

 it can do per foot of stroke is 



80 X 100 = 8, CCO foot-pounds. 



