1899] MEDITERRANEAN MILL MOTH. 89 



other connection, on each flat of the mill building. By shutting np 

 all doors and windows on each flat, and turning on the steam simul- 

 taneously to each floor, the whole building can be filled with live hot 

 steam sufficient to kill anything." 



In a letter written to myself by the owners of these infested 

 Canadian steam mills (a part of much correspondence which passed 

 between myself and Canada on the occasion of the attack), the loss up 

 to Sept. 29th was stated to be about £1000. 



By the above measures, modified, of course, to suit the require- 

 ments of different mills, the presence of infestation can be got under ; 

 but still there follows the almost absolute certainty that it ivill re- 

 appear, unless the most stringent measures are taken to prevent this 

 under the superintendence of someone well acquainted with the infes- 

 tation, and the signs of its presence in flour. The masses of spun-up 

 material which are the trouble in this attack are well described by one 

 of my correspondents as caused by a web or tissue, " which links, or 

 rather gathers together flour and other stock, forming a sponge, which 

 sometimes assumes such proportions that spouts are actually blocked 

 up. They are also a trouble at the feed-rollers, as they make the feed 

 to roller mills and other machines uneven, and might at such an 

 injury do vast injury to the plant." 



So far as I am aware, the only method of making a complete clear- 

 ance of the pest out of an infested mill, without almost prohibitory 

 amount of expense and trouble and publicity in the operations, is 



FUMIGATION. 



One great advantage of this treatment is that the fumes penetrate 

 into every cranny, and so reach the pest in its sheltering places, where 

 no mechanical measures would penetrate to it. But, on the other 

 hand, the treatment may greatly injure the flour left within sphere 

 of its action, or, again, may be dangerous in the extreme from in- 

 flammability. 



One plan recommended in the Canadian Bulletin, previously quoted, 

 is to subject the affected portions of a mill or building to repeated 

 treatment with the fumes of burning sulphur every night when the 

 works stop. If this is persistently carried out, it is stated that little 

 development of new forms (presumably continuation of development 

 from caterpillar to moth — E. A. 0.) will follow; but it is also stated 

 that abundance of sulphur must be burnt again and again to ensure 

 success. 



The effect, however, of the sulphur on the condition of flour stored 

 where it is exposed to its effect has been found to be so destructive to 

 its suitableness for bread making, that I subjoin a report received 

 from the owner of some large steam mills as a caution to those not 

 acquainted with the disasters that may arise. 



