EXACT PROOF 15 



state that "in a tent full of men, all apparently ill, 

 one may almost pick out the enteric cases by the 

 masses of flies they attract. This was very noticeable 

 at Modder River, for at that time there were in many 

 tents men with severe sunstroke who resembled in some 

 ways enteric (or typhoid) patients ; and it was remark- 

 able to see the insects hover round and settle on the 

 enterics. The moment an enteric patient put out his 

 tongue a fly would settle on it." Again, "At 

 Bloemfontein the flies were a perfect pest ; they were 

 everywhere, in and on every article of food. It is 

 impossible not to regard them as important factors 

 in the dissemination of enteric (typhoid) fever. Our 

 opinion is further strengthened by the fact that enteric 

 fever in South Africa practically ceases every year in 

 the cold weather, and this was the case at Bloem- 

 fontein." I can confirm the statement of the above 

 writers so far as Bloemfontein is concerned. There 

 the house-flies were a veritable plague, and the hos- 

 pitals and regimental tents and soldiers' lines were 

 actually swarming with them. No wonder the typhoid 

 played havoc with our Army. Pretoria told the same 

 story. Many other writers in various parts of the 

 world have reported similar observations regarding the 

 carriage of typhoid by flies. 



But all this evidence, though very suggestive, can 

 only be regarded as circumstantial or inferential. It 

 was not long, however, before more exact experimental 

 work brought new facts to light. The work of Celli 

 on the carriage of the typhoid bacillus has already been 

 mentioned. But in those days the germ of typhoid 

 was not so well known as it is now. Howard, who 

 is an established authority on entomology, gives the 

 following extracts as "exact" proof of the carriage 



