692 



THE POPULAR SCIENCE MONTHLY 



head of the population ; for Switzerland, 

 24; Germany 15; France 10. Turkey fig- 

 ures for only 0"2 of a letter per capita. In 

 America the number of letters and postal- 

 cards carried was '700,000,000 ; in Asia, 

 150,000,000; in Australia, 50,000,000 ; in 

 Africa, 25,000,000. 



Gas-Stoves and the Prodaets of Com- 

 bnstion. — City people are wont to express 

 their surprise at the stupidity of the coun- 

 tryman who extinguishes a gaslight by blow- 

 ing it out, and then sleeps in the same 

 room. Yet the same acute city people will 

 set up a gas cooking-stove, and will never 

 think of the necessity of carrying away the 

 products of combustion. Plainly, in view 

 of the prospective large employment of 

 carburetted hydrogen gas as a domestic 

 fuel, it behooves the sanitarian to empha- 

 size the necessity of proper regard for sani- 

 tary requirements. The public will have to 

 be instructed in the simplest elements of 

 science, and drilled to heed the plainest 

 teachings of every-day experience, or else 

 the general introduction of gas as a fuel 

 will at first occasion a fearful amount of 

 mortality. The observations of the editor 

 of the " Lancet," in a house in the " West 

 End " of London — the fashionable quarter 

 of that metropolis — might be repeated any 

 day in the " best quarter " of our American 

 cities. The editor of the " Lancet " visited 

 the kitchen of the house in question, having 

 been asked to give an opinion as to the 

 wholesomeness or otherwise of the cooking 

 arrangements. He found a gas hot-plate 

 with five circles of burners, each circle hav- 

 ing 12 or 15 jets, so that when the hot-plate 

 was fully heated 60 or 80 jets were in active 

 combustion. Each jet produced about two 

 cubic feet of carbonic acid per hour, a total 

 of 120 to 160 cubic feet, in addition to sul- 

 phurous acid. Xo chimney was provided for 

 the escape of the gas, and the very intelli- 

 gent inmates of the house could not under- 

 stand why the cook looked so pale and ill ; 

 as for the cook herself, though she often 

 felt " giddy and fit to fall upon the floor," 

 she never suspected the gas-stove! Now, 

 since each of the gas-jets had an effect 

 equal to the respiration of one human being, 

 it is evident that the population of that 

 kitchen practically amounted at certain 



times to sixty or eighty persons ; and the 

 exhalations from this " black hole " had no 

 way of escape except through the kitchen 

 door and into the house. This instance of 

 the stupidity of " intelligent " people is so 

 typical that it deserves to become " clas- 

 sic." 



Effects of a Diet of Sliingle-Nails.— The 



cows of a large dairy-farm in Hungary hav- 

 ing been all simultaneously seized with dis- 

 ease, the symptoms being high fever, diffi- 

 cult respiration, and inflation of the body, 

 it was determined to slaughter two of them 

 and to make an examination of the bodies. 

 The organs of the chest appeared perfectly 

 normal. On opening the stomach its con- 

 tents were found partly fluid and partly of 

 pappy consistence, and among this matter 

 were discovered a number of shingle-nails 

 of various lengths, some of them free, and 

 others partially imbedded in the walls of the 

 stomach. Renewed investigation cleared 

 up the mystery as to how these nails got 

 there. About a year before, a shed on the 

 estate caught fire, and the shingles of the 

 roof were torn ofl', nails and all, in the at- 

 tempt to put out the flames. In the winter 

 the damaged materials were burned in the 

 farm-buildings as fire-wood, the ashes sub- 

 sequently strewed upon a clover-field, and 

 the nails contained in the latter unfortu- 

 nately were raked up with the hay crop ob- 

 tained from it in the following summer. 

 Every cow upon the farm had to be slaugh- 

 tered, and in every case nails were found in 

 the second stomach. 



The Electric Light as a Source of Nitric 

 Acid. — It is known that, when combustion 

 takes place at high temperatures, small 

 quantities of the nitrogen and oxygen of at- 

 mospheric air combine, forming several ox- 

 ides of nitrogen, many of which are strong, 

 corrosive acids. This is the case when 

 electric sparks are passed through air, also 

 during combustion in air of hydrogen. It 

 therefore appears probable that, as the tem- 

 perature of the electric arc is undoubtedly 

 very high, nitric acid, or some other oxide 

 of nitrogen, might be produced by the elec- 

 tric hght. This subject has been investi- 

 gated experimentally by Mr. T. Wills, with 

 results strongly confirmatory of this theo- 



