Popular Science MordJdy 



891 



Stopping Mexican Bullets with 

 Sand-Filled Oil-Cans 



W 



''HEX residents of Naco, x\rizona, a 

 border town, began to barricade the 

 walls of their homes against Mexican 

 bullets, one man made a visit to the town 

 dump and obtained every' available 

 five-gallon coal oil can. These he 

 filled with sand and then built 

 a wall with them against 

 side of his house facing tl 

 Mexican line, about tv^-o 

 hundred yards distant. 

 About one hundred and 

 fifty of the cans were re- 

 quired but he had little 

 difficulty in finding this 

 number; for Naco, like 

 hundreds of other West- 

 ern towns, is a place 

 where coal oil is not sold 

 "loose," but is obtaina- 

 ble only in square tins 

 holding five gallons each. 

 When the task was 

 completed the man had 

 the equivalent of a solid 

 wall of sand a foot 

 thick along the side 

 of his home. During 

 a battle fought on 

 the Mexican side of 

 the town in Janu- 

 ar>% 19 1 5, when 

 the Carranza 

 forces holding 

 Naco, Sonora, were attacked by Yaqui 

 Indians, hundreds of bullets came across 

 the line and this unique barricade stopped 

 all that came its way. The homesteader 

 carefully repairs and refills any of the 

 cans that become damaged. 



Drilling Holes in Concrete with a Crank- 

 Operated Spring-Hammer Drill 



RILLIXG holes in concrete has always 



D 



The new type of crank-operated spring- 



hammer drill used as a 



quickened by the introduction of a new 

 type of crank-operated spring-hammer drill 

 which delivers fifteen hundred blows a 

 minute and uses hollow drills instead of star 

 or fluted drills. Hence all the material 

 removed is pulverized or ham- 

 mered to a dust. The device 

 may be used as a breast-drill 

 for holes in vertical walls 

 or for holes in ceilings or 



beams. 

 \ The drill consists of a 

 hollow barrel in which 

 reciprocates a piston or 

 hammer against the 

 compression of a spiral 

 spring at the handle 

 end. The movement is 

 produced by a ratchet- 

 wheel turned by two 

 hand cranks. As the 

 ratchet is revolved the 

 piston carrying the drill at 

 its free end is forced back 

 against the compression of the 

 spring. As the ratchet tooth 

 escapes, the piston jumps 

 back under the expanding coil 

 spring. The faster the ratchet 

 is turned the greater the num- 

 ber of blows transmitted to 

 the drill, which is rotated in 

 the usual manner. The ten- 



A solid wall of sand-hlled oil-cans forming a barricade a foot 

 thick along the side of the house facing the Mexican line 



breast drill 



its socket in 

 sion of the spring may be adjusted to vary 

 the force of the blows by means of a collar 

 bearing against the handle end of the 

 spring, this collar being moved in or out 

 through the medium of a threaded bolt 

 and outside thumbscrew. 



The device has a telescoping extension 

 for drilling holes in ceilings and the under- 

 sides of beams. It has found a 

 ready market among the firms mak- 

 ing and installing sprinkler 

 systems on account of the 

 ease with which the holes are 

 drilled for the supports to 

 hold the sprinklers in place. 

 Plumbers and heating and 

 electrical contractors make 

 use of it for drilling in con- 

 crete, brick walls or stone 

 for expansion bolts, pipe 

 hangers and the like. 



