method of collecting volcano gases 581 



An Attempt to collect the Volcano Gases before they reached 



the Air 



Be that as it may, in our effort to obtain samples of the gaseous emana- 

 tions from Kilauea for further study in this laboratory, it was a matter 

 of very great importance to us to endeavor to establish the facts in the 

 case without the aid of inferences of the character above outlined. We 

 therefore entered on a long study of the habit of the volcano, with the 

 purpose of going down on the floor of the crater directly adjacent to the 

 liquid lava, there to collect gases before they had come in contact with 

 the air at all. In the interval between May 1, 1912, and January 1 fol- 

 lowing but two favorable opportunities for such an undertaking occurred, 

 of both of which we endeavored to take advantage. On the first occasion 

 (May 28, 1912) a column of liquid lava had worked its way up through 

 the shattered floor adjacent to the large active basin and formed an active 

 lava fountain there several feet in diameter. Through its own spattering 

 this fountain quickly built for itself an inclosing wall or dike. When this 

 dike had grown to a completely inclosing dome (plate 19), the gases 

 discharged by the fountain were free to escape only through narrow slits 

 in the dome, and there they could be seen at night burning fitfully, with 

 a pale blue sheet of flame, thereby demonstrating (1) an excess pressure 

 within, and in consequence (2) that the gases released from the liquid 

 lava first came in contact with the air on emerging from these cracks in 

 the dome. 



We accordingly made the somewhat difficult descent into the crater 

 without mishap, and two crates, each containing 10 glass tubes of one- 

 half liter capacity each, arranged in a continuous series, were then lowered 

 down to us. To one end of this series of tubes a glass pipe-line was 

 attached, which led directly into one of the cracks of the dome (see 

 plate 20) through which the gas was escaping. The last link of the pipe- 

 line consisted of an iron tube extending into the dome about 12 inches. 

 'I'll is iron pipe was also lined with glass up to the very mouth of the crack, 

 so that, except for the 12 inches of iron pipe within the dome, the gases 

 came in contact with no substance other than cold glass and a few pure 

 rubber connectors, which were made as short as possible by abutting' tin 1 

 ends of the adjacent tube sections. Inasmuch as the liquid lava contains 

 nearly 10 per cent of FeO, the momentary contact of the gases with the 

 oxidized surface of the iron was not accounted a serious disturbing factor. 



The other end of the tube system was connected to a piston pump about 

 4 inches in diameter, with a displacement of about 2y 2 liters per stroke 

 to insure a rapid passage of the gases through the tube system. 



