ENTOMOLOGY

456 SANITARY ENTOMOLOGYrendered very attractive to house and blow flies and nearly all of thismaterial is wet when it is dumped and must have a day or two of hotweather in order to dry sufficiently to burn well. If it remains as long asfour days before burning, which is often the case during rainy weather,fly larvae have sufficient time to develop before the material becomes dryenough to be burned, and migrate to a nearby place where they enterthe ground and complete their life cycle.For the destruction·of paunch manure, etc., incinerators of varioustypes are used by some packing plants and stock yards. At Omaha,Nebraska, the Stock Yards Company has erected a huge incinerator ofa special type that contains sixteen large cells equipped with water pipesthroughout. As the contents of some of the cells are slowly burning, thewater pipes are heated and the hot circulating water dries the contentsof the freshly filled cells which are later also slowly burned. The ashesand charred material are then removed, mixed with finely ground, dry,sheep manure and sold for fertilizer. At least six men are constantlyemployed filling the cells and removing the charred contents and thereturns realized from the fertilizer are said to be sufficient to pay for alllabor and pay a reasonable amount of dividends on the investment o.f theincinerator plant, which was erected at a cost of $40,000.Other types of incinerators in use, which are operated mostly by packingplants for the disposal of paunch manure and refuse of all kinds, aresingle and double cell bridk structures where everything is completely consumedand the ashes are used for fillers of various fertilizers. At Chicagoone plant hauls all its paunch manure and refuse on railroad cars a shortdistance away to an incinerator made of a series of old discarded ironrails which slope from the top of the track embankment to the ground,leaving a considerable air space below. Here a fire is constantly keptburning and consuming the manure and waste piled on the rails above.Ashes filling the space below the rails are removed when necessary and aremixed with other fertilizers. At a few large plants the paunch manure isloaded daily on railroad cars and is shipped out two or three times aweek to places in the country where the manure is sold to truck farmers.The trackage beneath the cars along the loading docks is paved withconcrete to prevent full grown larvre from escaping from the loaded carswhen they are held over several days. The paving extends well aroundand beyond the length of the cars and near the outer edge it is providedwith a narrow, deep gutter filled to half its depth with water where it isconnected with the sewer. This arrangement carries off the excesswater and traps the maggots as they endeavor to migrate to a place forpupation.When treatment of infested dumps is necessary, borax solution orcrude oil is mostly used. Spent fuller's earth, a waste product from oil