ARRANGEMENT OF THE EXPERIMENTS. 



The methods of experiment were essentially the same as those 

 employed by Hasselbalch ^ in his light-bath investigations. 

 I respired into a metal funnel, which by the help of Stent's 

 composition fitted exactly on to the face, and thus, when smeared 

 with lanoline-vaseline, closed air-tight round the nose and mouth. 

 The funnel was connected by means of quite a short rubber-tube 

 with the valve-apparatus, a Geissler apparatus with valve of 

 thin guttapercha. The edge of the valves was fixed to the glass by 

 small pieces of sealing-wax. The inspiration was made through a 

 metal pipe, which was led up through the deck of the ship and 

 ended free; it was connected with the valve-apparatus by a rubber- 

 tube. From the upper bulb of the apparatus passed a short, 



I — '-shaped tube to a mixing- vessel surrounded by cold water. 



It may be mentioned, that whilst the tube of the funnel, as also the 

 valve and rubber-tubes were 2 cm. in internal diameter, the metal 

 lubes were only Г6 cm. No irregularities were noticed however in 

 the stream of air during the experiments, both the inspiration and 

 expiration proceeding quite without force. From the receiver a 

 short rubber-tube led to an ordinary, dry gas-meter, which indi- 

 cated litres. This gas-meter was controlled before leaving and was 

 found to indicate as much as 2 litres too little. Repeated experi- 

 ments on returning gave the same result, but it also proved that the 

 slower the air passed through it, the smaller was the error, and 

 that the meter, in the first minute after the stream of air had stop- 

 ped, itself partially adjusted the error, as the pointer moved a little 

 on. As the stream of air during the respiration-experiments flows 

 even slower than during the control-tests, there is reason to believe, 

 that the error in the given volumes of air is of no account. As 



1 K. A. Hasselbalch : Det kemiske Lysbads Virkninger etc. Hospitalstidende, No. 

 45, 46, 47. 1905. 



