4 



Scientific Proceedings (25). 



Increase in the total sulphur eliminated was marked on the day 

 of poisoning but, unlike the total nitrogen, returned to normal on 

 the following day. The neutral sulphur was increased both ab- 

 solutely and relatively to total sulphur on the poison day and that 

 following. A corresponding decrease in oxidized sulphur was 

 observed. 



3 (259) 



Pneumothorax and posture. 



By CHARLES A. ELSBERG. 



[From the Department of Physiology and Pharmacology of the 

 Rockefeller Institute for Medical Research."^ 



The sudden entrance of air into the normal healthy pleura often 

 gives rise to a train of grave symptoms. These symptoms have 

 been studied experimentally in dogs. Most of the animals died 

 from the pneumothorax when a large opening was made. Gluck 

 lost all of the dogs he used ; Biondi lost 4 of 5 ; Block, Marcus, 

 Schmidt, Pourrat and Rodet, Tuffier, Murphy, Quenu and Longet, 

 had similar experiences. 



In some recent experimental investigations of open pneumo- 

 thorax I obtained similar results. Many of the dogs either died 

 suddenly as soon as an opening into the pleura was made, or a 

 violent expiratory dyspnea ensued, soon followed by rupture of the 

 mediastinal septum, double pneumothorax, and death. The method 

 of operating on the dogs was the following : The animal was given 

 a hypodermic injection of morphin, and a few hours later was 

 anesthetized with ether ; tracheotomy was performed, a cannula 

 inserted, and the administration of ether continued through the 

 cannula. One or more ribs were resected, the intercostal muscles 

 divided, the pleura exposed, and a small opening carefully made in 

 it and gradually enlarged. In a number of the animals, the pres- 

 sure of the inspired and expired air was roughly measured by 

 allowing the animal to breathe into a large bottle, the tube leading 

 to it from the tracheal cannula being connected by means of a T- 

 tube with a water manometer. 



If a small opening (1-5 mm.) is made in the right or left pleura 

 of a dog which is lying on its back, or on its right or left side, the 



