Bacteriology of Septic War Wounds. 273 



and, if necessary, the jar re-exhausted. Finally, the jar is filled 

 with hydrogen, leaving a few centimetres of negative pressure, the 

 screw-clamps closed, the jar detached from the pump and cylinder 

 tubes and placed in the incubator. 



The process is considerably accelerated if the tubes containing 

 the media are boiled for half an hour previous to use. This form 

 of apparatus has given the most satisfactory results in my hands, 

 after an extended trial of many other methods. It is not very 

 troublesome, and has the advantage of simplicity. To obviate the 

 difficulty of condensation water on the surface of the agar, small 

 oblong pieces of filter-paper are kept ready sterilized, and one 

 placed under the lid of each plate before they are stacked in the 

 jar. 



Anaerobic Bacteria in Wounds. 



I will now proceed to a demonstration of three cases in which 

 a complete history will be shown photographically, commencing 

 with a radiograph taken shortly after wounding, and completed by 

 the radiograph taken when recovery had taken place. (The re- 

 production of these radiographs will be found in the paper by 

 Dr. Berry, "Archives for Eontgen Rays," December, 1916.) 



The amount of bacterial infection in a wound depends on many 

 factors — the site of the body injured, the amount of clothing 

 carried into the wound, the soil on which the fighting is taking 

 place, and to a great extent also on the time that has elapsed 

 before the wounded man has the parts cleansed and treated by 

 skilled hands. The velocity of the modern projectile is such that 

 in passing into or through human flesh and bone much minute 

 microscopical damage is caused to the tissues at some distance from 

 the actual wound, and if such a wound remain long unattended the 

 dead tissue forms a pabalum upon which the microbes carried in 

 by the projectile grow and flourish at an enormous rate. Fig. 2, 

 PI. XIX, is a pus-film from such a case ; the wound, a compound 

 comminuted fracture of the thigh, prevented the soldier, shot down 

 in an advance, from obtaining skilled aid for twenty-four hours, 

 during which time he lay in a shell-hole. This film was made on 

 the third day after he was picked up — that is, four days after the 

 actual injury. The pus is seen to contain a large variety of 

 anaerobic bacteria as well as aerobic species. Among the bacillary 

 forms are seen sporing organisms, and fig. 3, PI. XIX, shows a pure 

 culture of one of these organisms after careful plating and isolation 

 in the anaerobic chamber. The pus obtained from a wound may 

 perhaps at times not represent the actual state of tissue infec- 

 tion, for often the bacteria multiply in the pus itself, especially 

 when the discharge from the wound is pent up ; but, nevertheless, 



