880 



Popular Science Monthly 



form a solid, transparent, amber-like sub- 

 stance, odorless, heat-resisting, a non-con- 

 ductor of electricity, impervious to most 

 acids, oils and steam, and insoluble in all 

 known solvents. 



This substance is used for insulating, es- 

 pecially in automobile ignition work, since 

 it does not burn or soften when heated. 

 It also makes beautiful parasol handles, 

 fountain pens, buttons and numerous other 

 useful articles. The chemical name for this 

 jack-of-all- trades is oxy-benzyl-methylen- 

 ^lycol-anhy- 

 d ri te . 



Anothersub- 

 stance which 

 traces)its origin 

 back to the 

 shininglumpof 

 coal is ammo- 

 nia, important 

 in chemical 

 manufacture, 

 in refrigera- 

 tion, as a source 

 of nitric acid 

 and in fertil- 

 izers. Inks of 

 all sorts are de- 

 rived indirectly 

 from coal tar. 

 Among them 

 are printing 

 inks, ranging 

 from cheap 

 newspaper 

 black, made 

 from lamp- 

 black, to 

 thick heavy 

 paste used in 

 CO pperplate 

 printing. Col- 

 ored printing 

 and writing 

 fluids as well 



as typewriter ribbons and copying inks are 

 also made. 



Vanillin, which has the flavor of the 

 vanilla bean, is obtained from benzene. 

 Creosote is used as a wood preservative 

 and medicine. Benzaldehyde is the base 

 of many exquisite perfumes. Benzoic acid 

 is used as a food preservative and sac- 

 charin is a substitute for sugar, used 

 by diabetic patients. Phenacetine is a 

 drug used in controlling fever, and salicylic 

 acid becomes asperin, used for all sorts of 

 aches and pains. 



w 



Dr. Ludwig Oulmann, the New York skin specialist, 

 treating a case of baldness with ultra-violet radiations. 

 The lamp used may be regarded as a very intense 

 miniature sun. Twenty minutes' exposure sets up a 

 stimulating action which induces the hair to grow 



Artificial Sunlight for Bald 

 Heads 



''HAT causes sunburn? Not the heat 

 of the sun, but the light alone. It is 

 not the light that you can see but the light 

 that you cannot see — what the physicist 

 calls ultra-violet radiation. Just as there 

 are sounds that we cannot hear, so there 

 is light that we cannot see. If our eyes 

 were only differently constituted we might 

 see ultra-violet radiations. 



These ultra-violet radiations have very 



remarkable 

 curative prop- 

 erties. They 

 kill germs, and 

 they penetrate 

 the skin suffi- 

 ciently to set 

 up a wonder- 

 fully stimulat- 

 ing action. 

 Hence, special 

 lamps have 

 been con- 

 structed which 

 radiate ultra- 

 violet light and 

 which are used 

 for the treat- 

 ment of skin 

 diseases in par- 

 ticular. 



Since bald- 

 ness is a skin 

 disease, it fol- 

 lows that phy- 

 sicians have 

 been treating it 

 with ultra-vio- 

 let radiations. 

 The results are 

 often astonish- 

 ing. Many a 

 head as free 

 from hair as an 

 egg has been exposed for twenty minutes, 

 at intervals of three weeks, with the result 

 that in about two months down begins to 

 sprout. There are cases enough to show 

 that ultra-violet radiations restore prema- 

 turely gray hair to its natural color, 



A bald head exposed to ultra-violet 

 radiations appears in twenty-four to forty- 

 eight hours as if it has been sunburned. 

 In reality, it has — by an artificial sun of 

 great intensity. The skin peels and tans. 

 Nature is encouraged, as it were, to remove 

 the dead matter and to create new hair. 



