Vol. XXII. No. 9.] 



POPULAE SCIEN-CE NEWS. 



135 



l^ome, ifarm, anu tfsaruen. 



THE CHEMISTRY OF A MATCH. 



Although there are many people now living 

 who can remember the time when there were 

 no matches, and the uncertain and inconvenient 

 flint and steel w.as the only means of obtaining 

 fire, yet the inventor of the useful friction 

 match remains unknown. Like many other 

 great inventions, it is claimed by several differ- 

 ent persons. 



The most important substance used in the 

 manufacture of matches is phosphorus. This 

 singular element was first discovered in 16G9, 

 by Brand, a German chemist. It takes its 

 name from two Greek words signify- 

 ing the light bearer, owing to its 

 property of shining in the dark. It 

 was formerly only made in very small 

 quantities as a chemical curiosity ; 

 but, on account of the rapid growth 

 of the match-making industr}', manj- 

 tons are now annually produced, prin- 

 cipally from the phosphate of lime 

 contained in bones. 



Its most valuable property is its 

 intense affinity for oxj-gen, and the 

 ease and rapidity with which it unites 

 with that element, causing combus- 

 tion. It slowly oxidizes in the air 

 at ordinary temperatures, giving ofl' 

 luminous fumes in the dark, and at 

 167° F. it ignites. This compara- 

 tively low temperature — less than 

 that of boiling water — can readily 

 be attained by friction, and upon this 

 fact the usefulness of matches de- 

 pends. 



It is a well-known fact, that, when 

 botlies are rubbed together, heat is 

 produced. The heat developed in the 

 journal of a railroad-car is frequently 

 sufficient to set the packing on fire ; 

 and certain sav.ige tribes who are 

 ignorant of flint and steel, obtain fire 

 by rubbing two pieces of wood briskly 

 together. In such cases no heat is 

 created, — it is only motion trans- 

 formed. The heat which sets the packing of 

 a " hot box " on fire, comes as truly from the 

 coal burning in the furnace of the engine, as if 

 a burning coal had been taken and applied 

 directly to it. The only difference is, that the 

 effect is more indirect. The heat of the burn- 

 ing coal is transformed into motion by the 

 locoinotive, and the motion is converted back 

 intx) heat by the friction between the axle and 

 journal-box. The heat which the savage 

 obtains by rubbing the wood together, is 

 first developed in his body by the oxidation or 

 burning of his food, then is changed into the 

 muscular energy which he applies to the rub- 

 bing, and finally appears as heat again in the 

 igniting wood. 



It will thus be seen that the principle of fric- 

 tion is used in all the ordinary methods of 

 obtaining fire, and it is only in the amount 

 required that the modern methods are superior. 



The friction between the flint and steel is less 

 than that between the two pieces of wood, and 

 the amount of heat required to ignite a particle 

 of phosphorus is so small that a mere touch 

 will suffice. 



When phosphorus burns, it is converted into 

 a white solid substance known as phosphoric 

 anhydride (P^Os)- This is readily' fusible, and 

 coats every thing in its vicinity with a sort of 

 glaze, which prevents further combustion. 

 This would prevent the wood of the match 

 frpm readily igniting, so it is first dipped in 

 melted sulphur. Sulphur being quite inflam- 

 mable, only a very minute amount of phos- 

 phorus is necessary, which will not produce 

 enough phosphoric anhydride to interfere with 



the amorphous phosphorus and the chlorate of 

 potash. 



Matches have been made without using phos- 

 phorus ; mixtures of chlorate of potash, sul- 

 phide of antimony, and peroxide of lead, being 

 substituted : but thej' are inferior to those 

 containing the more fiery element, and have 

 never come into general use. 



its ignition. The flame of the burning sulphur 

 which only gives off a gas (sulphurous 

 anhydride) , is readily transmitted to the wood, 

 and the match is fairly lighted. 



A variety of phosphorus known as amor- 

 phous phosphorus is used in the manufacture 

 of safety matches. This has the same chemi- 

 cal composition as ordinary phosphorus, but 

 possesses very different properties. It will 

 only ignite at a temperature of 572° F. When 

 mixed with chlorate of potash, however, it 

 easily explodes. Safety matches are tipped 

 with a combustible mixture containing chlorate 

 of potash ; and the amorphous phosphorus is 

 spread upon one side of the box, forming 

 the igniting surface. When the match is 

 rubbed against it, the chemical combination 

 takes place, and the match is ignited. In 

 this case the fire is not produced entirely by 

 friction, but by the chemical action between 



THE EDELWEISS. 



The Edelweiss, or " noble white " {Gnapha- 

 lium Contopodium) , is a beautiful little pearly- 

 white flower growing upon the Alps and Pyre- 

 nees, at an altitude of about six thousand 

 feet. It is much sought after by Alpine 

 mountaineers, and is proudly worn by 

 the adventurous climber as a badge 

 of daring and bravery. Unfortunately, 

 however, it is extensively collected 

 and sold by the Swiss peasants ; so 

 that many a traveller, with his hat 

 picturesquely decorated with a bunch 

 of the flowers, may never have made 

 a mountain expedition involving more 

 danger than a trip over the Eigi Rail- 

 way, or a carriage-ride over the 

 Simplon Pass. 



The practical Germans also make a 

 very perfect imitation of the Edelweiss 

 out of cotton- wool, which doubtless 

 answers the purpose of the average 

 Alpine tourist just as well as the 

 original flower. 



Like many other Alpine flowers, the 

 demand for specimens is so great that 

 it is becoming scarce, and is in dan- 

 ger of extermination. In "order to 

 avoid this undesirable result, a botanic 

 garden has been founded in Geneva, 

 where all the rarer Alpine plants are 

 preserved, and specimens supplied to 

 botanists and collectors. 



The Pklelweiss can be cultivated in 

 pots, or among rockwork ; but it is 

 said that when transferred to a lower 

 level, its blossoms sometimes become 

 red. Among the Swiss mountaineers 

 it is considered the emblem of puritj-, 

 and is used as a bridal flower in place of the 

 orange-blossoms of more temperate climes. 

 An allied species, the G. Supinum, is found 

 on the summit of Mount Washington and a 

 few of the highest peaks of the White Moun- 

 tains. The common cudweed, or everlasting, 

 also belongs to the same family. 



HOPS, 



The hop-plant is, in many sections, a crop 

 of great importance. Its principal use is to 

 impart a bitter flavor to beer and ale, though 

 its active principle, kipulin, is used to a con- 

 siderable extent in medicine. It is a graceful 

 and handsome vine, and is sometimes culti- 

 vated as an ornamental plant ; but it tends to 

 grow coarse and ragged in the latter part of 

 the season. 



The hops themselves are the catkins of the 



