Show among bothersome dusts silica said to be cause of disease known as silicosis dust is never a pleasant thing to breathe but some dusts are far worse than others coal dust for example may color a miner s or coal heaver s lungs as black as night but it rarely does anything more serious states a writer in the chicago tribune on the other hand the repeated inhalation of freshly ground silica dust silica is a general er al name for the compound that makes up sand and quartz fre results in a disease known as silicosis characterized by an ex scarring and destruction of lung tissue this disease has come to be rec as a serious industrial haz ard since sand and quartz are obviously quite nonpoisonous as found in nature the fact that they are more dangerous than other dusts when finely ground led to the suspicion that silicosis was a re suit sult of some hitherto unrecognized property of silica tests on rabbits appear to have shown that the danger can be greatly lessened if the silica dust is mixed with a trace of metallic aluminum dust silica is a compound of the ele ments 0 of si silicon icon an and oxygen and the atoms of these elements are so arranged on the surface of freshly broken silica that the oxygen atoms possess a small but definite part of the combining power of free ele ment presumably this is responsible for the fact that freshly ground silica is more soluble than other forms of the material this in turn suggests that the deadly effect of silica dust is the result of its actually combining chemically with the lung tissues and not of mere mechanical irritation it if this were true the way to de nature silica dust would be to bring it in contact with something that had a greater affinity for oxygen so that the latter would be completely saturated before it had time to attack living tissue theoretically aluminum should have such an et ef feet and tests with it have borne i out these predictions |