116 PROCEEDINGS OF THE AMERICAN ACADEMY. 



boring passed a right-angled hard glass tube, terminating in a spiral, 

 which could be heated by a broad burner. The other boring held an 

 exit tube passing to a solution of potassic hydroxide. Gas jets were 

 kept burning in the room, and air, at a temperature from 16 to 60°, 

 was drawn from the bottle through the solution. Several trials were 

 made, each lasting one hour, and in no case was arsenic detected. 

 How the arsenic was tested for is not stated, but it is not surprising 

 that none was found. The absurdity of the experiment was shown by 

 Taylor* a week or so later. 



Abel,f in the same year, made the following experiments at the 

 instance of the British government. A room was selected having a 

 green unglazed paper containing one fifth of a grain of arsenious oxide 

 per square inch (20 grams per square meter). 



1. The room was closed for 36 hours, and then the air was led 

 between four and five hours through a solution of argentic nitrate, and 

 then through a tube containing asbestos soaked in ammoniacal argen- 

 tic nitrate. No arsenic was found in solution or tube. 



2. Five gas flames were burned in the room for several hours, and 

 at the end the air was led through the same reagents with the same 

 negative result. The method used in testing is not given. 



3. A glass tube, 3.5 ft. long and 2 in. in diameter, was filled with 

 small pieces of arsenical paper, warmed to 32°, and connected with 

 the reagents as above. The air of the room was led through for a 

 week, and from time to time gas burners were lighted. 



4. The air was passed through a strong solution of sulphurous acid 

 and then led for 24 hours through the apparatus. 



5. The products of combustion of a gas burner were concentrated 

 by a funnel and led through the apparatus for three days, and again 

 (6) for four days. 



7. The paper was roughened by friction and hot air led through 

 for nine days. 



8. Strips of arsenical paper with decomposing paste were placed in 

 the same tube, and hot air led over for nine days, with products of 

 gas combustion also. In none of Experiments 3 to 8 was arsenic 

 found in either silver solution or tube. Yet as the method of test- 

 ing for arsenic is not given, and we do not know its accuracy, the 

 experiments are thus deprived of considerable value. 



* Pharmac. Journ. and Transactions, 1858, p. 553. 



t Ibid., p. 556 ; also British Review, October, 1858, and Schmidt's Jahrbuch, 

 1859, XLV. 20. 



