100 



Popular Science Monthly 



Modern Methods for Exterminating 

 the Mosquito Pest 



NEXT to draining, the best way to 

 atjolish mosquito breeding places 

 is to treat the water so as to kill the 

 mosquito larvae. While many sub- 

 stances have been tried for this purpose, 

 nothing has given such good results as 

 petroleum, according to experts of the 

 United States Department of Agricul- 

 ture. Common kerosene of low grade 

 is most satisfactory as regards efficiency 

 and price. 



It has been found that spraying with 

 a portable pump is the best way to use 

 the oil. Small ponds, however, can be 

 sprinkled out of an ordinary watering- 

 pot with a hose nozzle, or for that 

 matter pouring it out of a dipper or cup 

 will be satisfactory. In larger ponds 

 pumps with a straight nozzle may be 

 used. A straight stream will sink and 

 then rise and the oil will spread until 

 the whole surface of the water can be 

 covered without waste. 



In choosing the grade of oil to be used 

 two factors must be considered; it 

 should spread rapidly and should not 

 evaporate too r|uickly. Heavier grades 

 of oil will cling together in spots and the 

 coating will be necessarily thick. It has 

 been found that one ounce of kerosene 

 is sufficient to cover fifteen square feet 

 of surface, and in the absence of wind, 

 such a film will remain persistent for 

 ten days. Kven after the iridescent 

 scum apparently disappears there is still 

 an odor of kerosene about the water. 

 A mixture of crude oil and ki>rosenc has 

 been found to be effective in killing 

 mosquito larvae. It has one advantage 

 over pure kerosene in that it does not 

 evaporate so cjuickly. 



S])ecial attention should be paid id 

 little pockets of water that form around 

 the edges of ponds, for it is in sucli 

 places where the water is not disturl)ed 

 l)y wind or otherwise that the larvai' 

 breed in greatest numbers. Larvae do 

 not breed in open stretches of water 

 where the surface is rippled by the wind. 



In the fight against the mosquito in 

 Panama, the governiuenl experts found 

 that a larvicide coiuposed of carbolic 

 acid, rosin and caustic soda was very 

 effective and lliousands of gallons ol il 

 were used. 



Threshing by Night Under 

 Electric Light 



THE farmer like the city man does 

 not allow daylight to put a quietus 

 on work. On the other hand he labors 

 into the night just as assiduously as the 

 city man, and makes hay not only while 

 the sun shines on this side of the earth, 

 but while the sun shines on the other 

 side, too. With the aid of a new portable 

 generator recently placed on the market 

 he can do his threshing at night, and do 

 it with a degree of thoroughness not 

 excelled in the brightest sunlight. 



The dynamo is drawn up beside the 

 thresher and is driv^en by a belt from the 

 threshing machine. The apparatus is 

 sufficiently powerful to light at least one 

 arc light, which throws a brilliant white 

 light on the field of operations. When 

 the farmer finds the spring thawing 

 season suddenly thrust upon him and the 

 ground ready to be plowed he can work 

 far into the night with the aid of the 

 same portable generator. It sup]5lies 

 light for two projecting lamps, one in 

 front to light the way, and the other in 

 the rear to show the plowed area. 



Uncle Sam Says Miraculous Wheats 

 Are an Old Delusion 



THE notion that tiicre is a wonderful 

 wheat which will make the fortune 

 of anyone who plants it seems to be al- 

 most as old as agriculture itself. In this 

 country, at least, such an assertion was 

 made for the so-called Jerusalem wheat 

 as early as 1807, and, imder the name of 

 Alaska wheat, this identical variety is 

 still being pushed upon the unwary at 

 exorbitant prices for seed. Almost 

 equally exaggerated claims are made for 

 the Stoner variety, but this particular 

 wheat has not such a long history. 



Recanse of the many attempts that 

 ]\,\\v been made by promoters to foist 

 these wheats, under one name or another, 

 upon the farmers of the country, the 

 Deiiartment of Agriculture has made 

 careful tests of their ^•alue. The re- 

 sults of these tests arc saitl to show con- 

 clusively that neither of the wheals 

 ])ossesscs any peculiar (|ualil\' which 

 justifies high jirices for the seed. Many 

 \arielies grown connnercialh' throughout 

 tile counlry ha\'e pr()\'ed to be superior 

 to either the Alaska or the Stoner. 



