Popular Science Monthly 



8G1 



^Catch operMrvg 

 ring 



and alone. On contact patrol, planes 

 fly very low and have done such effect- 

 ive work particularly with their ma- 

 chine-gun fire, that the Germans have 

 found it necessary to dig bullet-proof 

 trenches alongside the roads on which 

 their troops march. At 

 the alarm, the regiments 

 dive for these trenches 

 where they are com- 

 paratively safe. 



Generally five planes 

 are assigned to a con- 

 tact patrol squadron. 

 They fly in the usual 

 V-shape formatic^. 

 Once over the lines, 

 their work commences. 

 They remind one of 

 hawks hovering over a 

 chicken yard. Eagerly 

 the pilots and observers 

 scan the ground below, 

 undaunted by the hail 

 of lead poured up at them 

 from machine-guns and 

 "Archies." 



will be hidden in them with the result that 

 perhaps one or more planes of the squad- 

 ron will be brought down by their fire. 

 Hostile ammunition and gasoline depots, 

 headquarters, railway junctions, detrain- 

 ing stations and aircraft hangars are 

 all objectives for the 

 pilots of a contact pa- 

 trol squadron. It may 

 be that there is a de- 

 tachment of enemy en- 

 gineers busily engaged 

 in preparing the site 

 for a new battery or 

 building a bridge. If 

 seen, rest assured that 

 the planes will give them 

 a warm reception. 



Clvjmp of 

 steel ^rows 



m 



IMeial 



Submarine Saws for 

 Water Weeds 



A 



What's That? A Regi- 

 ment of Germans ? 



What the observers 

 in the machine want to see most is a 

 train or railroad or road-bridge. As soon 

 as they see one, down they swoop. One 

 after the othei* lets go a load of bombs and 

 climbs again. The observers note the 

 damage, etc. Suppose they see a regi- 

 ment marching rapidly towards the front. 

 In a fast glide, they descend almost on 

 top of the startled soldiers. The machine- 

 guns mow the Germans down, and often one 

 plane of the squadron, flying higher than 

 the rest, releases several 

 clumps of the steel arrows. 

 If there are 

 no safety tren- 

 ches at the 

 side of the 

 road, it is pos- 

 sible that al- 

 most the whole 

 regiment may 

 be \\iped out. 

 Should there 

 be trenches, 

 no doubt 

 machine-guns 



These arrows, dropping from 

 a great height, have consider- 

 able penetrative force, but a 

 steel helmet affords Drotection 



The saw, from loO to 300 feet long, cuts the weeds; a 

 wooden grating collects them and a rake removes them 



SUBMARINE 

 saw is used to 

 clear weeds from irri- 

 gation canals on the 

 project of the United 

 States Reclamation 

 Ser\ice at Orland, Cali- 

 fornia. It is five-six- 

 teenths of an inch wide, 

 one-fiftieth inch thick, and the teeth are 

 spaced seven-sixteenths of an inch apart. 

 It is made of special steel in flat, flexible, 

 tape form and has toothed edges. Two 

 men. one at each end, operate the saw by 

 means of ropes, starting at the lower end 

 of the section to be cleared and working 

 up-stream. The saw is placed diagonally 

 across the stream, one man keeping 

 slightly ahead of the other. It is held at 

 the bottom of the canal by iron weights 

 placed at intervals of about 

 three feet. To remove the 

 weeds, planks 

 are placed 

 across the 

 banks, about 

 six inches 

 above the sur- 

 face. Slanting 

 wooden pieces 

 project into 

 the water form- 

 ing a grating 

 which catches 

 the mo^^Ti weeds. 



