514 



AGRICULTURAL ENGINEERING 



Efficiency of gasoline lamps. 



Kind of lamp 



Where tested 



Candle 

 power 



Candle- 

 power-hrs. 

 per gal. 



Cost per can- 

 dle-power- 

 hour at 20c. 



Bracket lamp 

 Hanging lamp 

 Pressure lamp at 34 lbs. 



Underneath generator 



la. Exp. Sta. 

 la. Exp. Sta. 

 la. Exp. Sta. 



Pa. Exp. Sta. 



51.2 



65.5 



300.0 



36 to 43 



2948 

 3180 

 4550 



1885 



.0068c 

 .0063c 

 .0043c 



.0120c 



Fig. 314. A gasoline lamp. The tubini 

 coiled so as to appear in the pic- 

 ture. 



QUESTIONS 



1. What are the improved 

 systems of lighting? 



2. How were houses light- 

 ed by artificial means in early 

 times? 



3. What is the common 

 unit of light, and explain how 

 it is established? 



4. Explain how the illumi- 

 nation of any source may be 

 measured. 



5. What are the advan- 

 tages and disadvantages of 

 kerosene lamps? 



6. What effect does the 

 use of a mantle have upon 

 the efficiency of* lamps? 



7. Discuss the merits of 

 gasoline lamps. 



8. How does the cost of 

 light from kerosene, alcohol, 

 and gasoline lamps compare? 



9. Estimate the cost of 

 lighting the average farm- 

 house during a period of one 

 year with the different 

 systems. 



