Popular Science Monthly 



579 



After the patient has been in the bath for 

 about eight minutes his forehead will be 

 covered with a slight moisture and his 

 respiration will become accelerated. After 

 a time, varying from fifteen to thirty 

 minutes, the wax is removed from the 

 entire body and the invalid then lies down 

 and rests. 



The fact that he is not burned always 

 causes the patient a great deal of astonish- 

 ment. The real reason is that wax has a 

 very slight capacity for holding heat. 

 Although it becomes ver>- hot during the 



melting process it loses its heat almost 

 immediately upon being removed from the 

 flame or from over the steam. Con- 

 sequently, although it is boiling hot when 

 it leaves the spout, and is still hot enough 

 to be poured when it reaches the body, it 

 is not sufficiently hot at the moment of 

 contact with the flesh to burn it. 



This new wax cure has been recom- 

 mended as a means of aiding soldiers to 

 recover the use of joints which have been 

 stiffened through injuries received in the war. 



A patient completely immersed in a wax bath from chin to heels. The basket couch is lined 

 with a material impervious to wax. In this he lies, perspiring freely, for a specified time 



A Perfume Spray from a Penny 

 Slot Machine 



ANEW slot machine has made a bid for 

 popularity on some of our street 

 corners and railway stations. For only one 

 penny deposited in the slot you can spray 

 your clothing or your pocket handkerchief 

 with perfume of any preferred odor. The 

 mechanism is simple. After dropping the 

 coin in the slot, you press a lever in the 

 usual way. This operates a bellows, forc- 

 ing air through the perfume container and 

 producing the spray. The weight of the 

 coin passing down through the chute, over- 

 balances a latching device and moves it 

 away from the lever, while a movable arm 

 drops to allow the bellows to operate. 



It may be true that those who delight in 

 the perfume of the heliotrope, the violet and 

 the rose, and who occasionally neglect to 

 provide for their olfactor>' satisfaction 

 before leaving home, may bless the ma- 

 chine; but there are those to whom the 

 thought of a dozen diff^erent perfumes 

 mingled with the stagnant air of a crowded 

 car is anything but pleasant. However, 

 the amount obtainable for the penny in- 

 serted In the slot is not likely to be sufficient 

 to be objectionable. 



Why Does Oil Poured on the Waters 

 Calm the Sea ? 



WAVES in mid-ocean are caused entire- 

 ly by the action of the wind. The 

 adhesion between the rapidly moving par- 

 ticles of air which compose the wind and the 

 surface particles of the water causes the 

 water's surface to be dragged along with the 

 air. Small ripples are immediately formed. 

 These ripples soon overtake others near 

 them. They unite, and due to the friction 

 between the water particles, each succeed- 

 ing ripple piles up on the top of previous 

 ones. 



Just as soon as oil is spread up>on the 

 water, however, the size of the waves is 

 reduced like magic. The reason for this is 

 interesting. Oil, unlike water, has ver>' 

 little internal friction between its particles. 

 The ripples of oil formed by the wind, there- 

 fore, cannot pile upon each other to any con- 

 siderable height. Hence, water waves can- 

 not grow in an area of oil placed about a 

 steamer. They begin to fall down instead. 

 By the time these waves reach the boat they 

 will have lost their formative ripples and 

 the result is a perfectly calm surface over 

 the portion of the sea through whJch the 

 boat is making its way. 



