306 CAPT. J. DAVIDSON. 



In this way these public areas, which are liable to be neglected, were kept clean, 

 and possibilities of fly-breeding reduced to a minimum. 



V. Disposal of Dead Animals. 



Blue-bottle flies were only occasionally met with in any numbers on the desert, 

 largely owing to the care taken in disposing of dead animals and the incineration of 

 all used bully-beef tins, etc. 



Dead camels, horses, and mules were dealt with as follows : — At the selected 

 burial ground a large pit about 6 feet deep was dug, into which was put some old 

 sacking, tibbin, firewood, etc., saturated with oil. Two or three stout iron bars were 

 placed across the pit. The carcase was disembowelled, the cavity being filled with 

 tibbin or old sacking saturated with oil. The legs were cut off and the prepared 

 carcase placed over the pit on the iron rails. Oil was then poured over it and the 

 whole set on fire. Gradually the remains of the carcase falls into the pit and when 

 the fire is spent it is filled in. 



A definite burial ground is established at every large camp, to which all dead animals 

 must be taken and disposed of as described above. 



VI. Destruction of Adult Flies. 



In addition to the treatment of breeding places, the destruction of adult flies was 

 vigorously carried out by means of the following methods : — (1) By spraying with 

 various solutions ; (2) by wire coated with tanglefoot ; (3) by fly-traps ; (4) by 

 poisoned bait ; (5) by fly flappers. 



(1). Spraying with solutions. — Flies congregate in mess huts, mess tents, canteens 

 and cook-houses, being attracted by the food and shade. These places were closed 

 up and the flies sprayed with Lefroy's fluid (pyrethrum basis), or Osbeer's fly 

 solution (Flybane), by means of a fine atomised spray, until the atmosphere was 

 almost saturated. The flies fell to the ground dazed and helpless and were readily 

 destroyed. Blockhouses were also treated in this way. 



Often during the Khamseen winds, flies collect in great numbers on the lee side of 

 canvas latrine screens, rush matting walls of cook-houses, etc. A soap-paraffin 

 emulsion or a strong solution of cresol (about 10 per cent.) sprayed very forcibly and 

 quickly on them with a Mackenzie sprayer was useful. They fell to the ground and 

 were easily killed. 



(2). Tanglefoot fly wires. — Tanglefoot was made by heating commercial castor oil 

 almost to boiling (not boiling), and stirring in powdered resin until the mixture 

 became a black sticky mass. The proportions used were : castor oil, 4 pints ; resin, 

 9 \ lb. It was Tound necessary to alter the proportion of resin slightly according to 

 the time of the year. During the cold nights of the later part of the year, if too great 

 a proportion of resin is used, it tends to crystallise out on the wires and the tanglefoot 

 'oses its tackiness. Pieces of wire were cut into lengths of 18-24 inches, coated with 

 tanglefoot (applied when hot and the wires slightly heated), and hung up in tents, 

 cook-houses, etc. Flies delight to rest on pieces of hanging wire or string, and very 

 great numbers were caught on these wires. During the day-time the wires should be 

 hung low down in the tents and high up towards evening. Flies always go to the top 



