94 



Popular Science Monthly 



Trenches are now excavated and filled by machines. The filling-machine operates the 

 scraper at a rate of speed wholly beyond that attainable by a man and a team 



Filling Trenches by Machine 

 AN advance step has been taken 

 ±\ in the construction of sewers and 

 the laying of water-mains. With the 

 modern trench-filler no time is lost in 

 refilling the excavation. The contents 

 of the deepest and longest earth opening 

 can be put back in double-quick time. 



The new machine is a gasoline-engine 

 which drives a windlass by means of 

 which a steel cable is wound. To the 

 end of the cable is attached a steel 

 scraper. The engine and equipment are 

 mounted on a movable truck. Such is 

 the construction that the machine can 

 be used either on the truck or can be 

 removed entirely by simply taking 

 several bolts out of the turntable. 



The new apparatus readily adapts 

 itself to several other uses in connection 

 with trench operations. It is used to 

 pull heavy cables through conduits, to 

 raise and lower giant telei)hone poles 

 into their rcsi)e(ti\e places, as well as 

 to load and iniload pi|ie and place it 

 in trenches. 



The engine is of four and a half horse- 

 power. It operates the scraper at the 

 rate of one liundred and fifty feet per 

 minute in ordinary soil and one hundri'd 

 feet per minute in heavy clay. The 

 speed is regulated to suit the .soil by a 

 change of sprockets on the engine's 

 crankshaft. 



The crew for oix-ration consists of 

 two men — one to pull the lever control- 



ling the windlass and the other to 

 handle the scraper. The instant the 

 scraper reaches the edge of the trench 

 the power is released, and the helper 

 draws the empty scraper back to 

 position ready for another load. 



The Amazing Beetle 



ONE of the most amazing things in 

 natural history is the way in which 

 beetles have triumphed in the struggle 

 for existence. Of all creatures they are 

 by far the most numerous, no fewer than 

 150,000 distinct species having been 

 identified — three times the number of 

 backboned animals. 



Beetles are wonderfully adaptable. 

 They are found practically ever\-where 

 — in the frost-bound tracts of Iceland 

 and in the hot desert sands of Africa; 

 on the highest mountains, under the 

 ground, and as fossil, in the deepest 

 strata; on land and in water: on plants, 

 among stones, and in wood antl earth; 

 and even in the very craters of volcanos. 



But there is one place where no 

 beetle has yet been found — it is the 

 inhosjiitable land of Spitzbergen, to 

 the north of Russia. Here are mam- 

 mals, birds, fish, molhisks, crustaceans, 

 a few insects of varied s|X'cies, and 

 man>- spiders, but not a single beetle. 

 While other insects have succeeiled in 

 some way in migrating from the main- 

 land, the beetles have apparently been 

 unable to cross the wide, icy waters. 



