THE PROGRESS OF SCIENCE. 



95 



small percentage of volatile combusti- 

 ble matter. Commercial anthracite 

 varies from the hard, dry Lehigh with 

 little more than one per cent, to the 

 easily lighted Bernice coals of Sulli- 

 van county, Penn., with ten per cent. 

 The Lackawanna and Lykens Valley 

 coals, so much prized for domestic use, 

 are midway between Lehigh and Ber- 

 nice. The use of hard coal has be- 

 come so well-nigh universal in the 

 eastern towns and cities that one hard- 

 ly understands how the community 

 could become accustomed to the use of 

 soft coal; yet the available supply of 

 anthracite in America is so small that, 

 unless some other fuel be discovered, 

 the use of bituminous coal must pre- 

 vail within seventy-five years at the 

 most. The anthracite fields of Penn- 

 sylvania will be exhausted within 

 seventy-five years, even though the an- 

 nual production should not exceed that 

 of 1901 which is improbable. There 

 is no other deposit of anthracite in the 

 United States, aside from some wholly 

 unimportant patches in North Carolina, 

 New Mexico and Colorado, so unimpor- 

 tant that all combined would yield hard- 

 ly enough for one year's consumption. 

 Europe has very little anthracite. Most 

 of the Welsh coal is bituminous, the 

 anthracite of the South Wales field 

 being confined to the western end of 

 that field. The Worm basin of Prus- 

 sia yields perhaps 2,000,000 tons per 

 annum of a semi-anthracite; near 

 Ostrau in the Silesian field and in the 

 Donetz field of south Russia anthracite 

 occurs in moderate quantities; but 

 these are all unimportant. China, 

 however, has vast fields compared with 

 which our Pennsylvania fields are mere 

 dots on the map; there being upward 

 of 40,000 square miles underlain by 

 anthracite coals in Hunan, Honan and 

 East Schansi. 



BORAX AS A FOOD PRESER- 

 VATIVE. 

 The question of the use of borax and 

 boric acid as food preservatives has 



attracted much attention of late, es- 

 pecially in Germany, where it has been 

 brought forward as a convenient lever 

 to exclude American food products. 

 The results of different investigators 

 are far from uniform, and the conclu- 

 sions drawn as to its use are corre- 

 spondingly at variance with each other. 

 It is generally conceded that as far as 

 regards digestion neither borax nor 

 boric acid have any specific influence, 

 but when considerable quantities are 

 present the alkalinity of the former 

 or slight acidity of the latter may be 

 of some effect. In a similar way they 

 may act as mild irritant poisons, occa- 

 sioning diarrhoea. With continued use 

 most observers find a loss of weight, 

 which seems to be due to loss of fat 

 in the body, and this may occur, with- 

 out any symptoms of ill health, when 

 small quantities of borax or boric acid 

 are ingested daily. It is possible that 

 this result might attend the regular 

 use of food products which have been 

 preserved by boric acid. While the 

 quantity of the acid present is usually 

 quite small, it is completely eliminated 

 from the system rather slowly. In 

 doses of three grams, one half was 

 eliminated in the first twelve hours, 

 but from five to nine days were re- 

 quired for the disappearance of the 

 remainder. In this way boric acid 

 might have the effect of a cumulative 

 poison. It is said to be a common 

 practice in this country to preserve 

 butter and meat by packing in a mix- 

 ture of salt with some borax or boric 

 acid. Such a mixture was the ' rex 

 magnum ' largely sold fifteen years or 

 so ago. Recent experiments by Polen- 

 ske show that fat takes up very little 

 of the borax powder, while meats take 

 up no inconsiderable quantity. Ameri- 

 can pork was found in one case to have 

 absorbed in its outer portion no less 

 than two per cent, of its weight of 

 borax, while in another case four per 

 cent, was taken up in three weeks. 

 This latter amount may, however, be 

 considered extreme. In this connec- 



