Popular Science Monthly 



31 



the gunners would have to depend upon 

 the gun's telescopic sights, and there 

 would be no checking up of hits or misses 

 by the spotters in the mast tops. 



Thus, the means of communication is 

 the crux in the modern method of pointing 

 and firing a battleship's guns. In our 

 Navy, voice tubes are generally preferred 

 to electrical apparatus. Speaking tubes 

 are just metallic pipes made airtight. 



Why Do You 



Laugh When You 



Are Tickled? 



ALTHOUGH it 

 .is usually 

 done in fun, the 

 habit of tickling is 

 supposed to be a 

 somewhat danger- 

 ous one, according 

 to physicians. The 

 ticklish areas are lo- 

 cated over the least 

 protected parts of 

 the body, where 

 delicate vital or- 

 gans are to be pro- 

 tected. The reason 

 for the ticklishness 

 is that the skin is 

 highly sensitive 

 there and "aware" 

 of intrusion, as a 

 means of protec- 

 tion from possible 

 injury. 



This sensitive- 

 ness, or awareness, 

 the physicians say, 

 is a relic of the days 

 when man's pre- 

 historic ancestors had to guard their lives 

 constantly against creeping insects and 

 the hea\-y' penetrating pressure of animals' 

 teeth. That is why, according to this 

 theory, the tickle reflex is elicited prin- 

 cipally by a light running motion over 

 the skin, and by sudden prods. 



The reaction, in this age, is a \'iolent 

 discharge of energy in the form of laugh- 

 ter and efforts to be free. But it is easy 

 to imagine the shrieks of terror or pain 

 that might have been the forerunner 

 of the laughter. Humanity takes ages 

 to outgrow its prehistoric impulses. 



The highly compressed gas in the "bomb," 

 on being let out through the "buoy," 

 forces out the combustible oil with it 



The Liquid Fire of the Trenches Is 

 Not as Deadly as It Looks 



THE effect of jets of liquid fire on 

 men in the trenches is more terrible 

 to the eye than to the body. But despite 

 this fact, it is still used as a weapon. 

 The bulky, rectangular tanks found in 

 the original outfits have been replaced 

 by the less cumbersome and more efficient 

 "life buoys" and 

 "bombs" of the lat- 

 est flame projec- 

 tors. In operation, 

 the Germans let 

 out the gas under 

 compression, so 

 that it forces a 

 stream of combus- 

 tible oil from the 

 buoys through a 

 connecting line of 

 hose. The oil, 

 which travels fast 

 under the great 

 pressure, passes a 

 lighted wick in 

 the nozzle of the 

 hose. The burning 

 jet is then direct- 

 ed toward the 

 enemy. 



But improve 

 their apparatus as 

 they may, the Ger- 

 mans have no con- 

 trol over the ac- 

 tion of the air. 

 By lying flat at 

 the rear of their 

 trenches, the men, 

 being attacked, are 

 in little danger. It 

 is the German soldier who has suffered 

 most from fire. The British, in self- 

 defence, have combated liquid fire with 

 the flaming shell. This, as explained 

 in the October issue of the Popular 

 Science Monthly, does not ignite until 

 it hits the ground. If the guns are 

 pointed so that the shell strikes just 

 in front of the trenches, both flames 

 and debris will shower over the enemy 

 troops. Moreover, the British have 

 found that by firing at the enemy's 

 tanks, these are often exploded, killing 

 their operators in the action. 



