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been found to answer well (or at least to have been 
followed by absence of Fly) in instances recorded, but 
instances are also given of some of these and other 
applications being of little if any benefit. 
The great difference in these results suggests that the 
effect may depend in part on the state of the weather 
and of the ground at the time of application, and that 
the preventive effect arises from the scent or the pre¬ 
sence of the steep or dressing making the ground, or 
the young plant coming up through it, obnoxious to the 
Fly, or prevent it being attracted by the peculiar smell 
of the food-plant, on which subject I wish to offer a few 
words presently. In hot and dry weather scent would 
diffuse itself gradually, and dustings or dressings of lime 
and soot remain serviceable, whilst in the case of heavy 
rain the dressings and the scent would be removed 
together. This effect of rain was shown last year in an 
instance where a mixture of equal parts of carbolic 
powder and sulphur with a small proportion of soot 
were used to drill with the seed ; the mixture kept the 
Fly away until rain washed it off, and then the plant 
was attacked and destroyed. 
Another possible method of action of some of the 
steeps (which is open to proof or disproof by analysis) 
is such absorption of the diluted steep taking place by 
means of the rootlets as makes the plant unsuitable for 
food for the Fly. This is a matter for minute chemical 
investigation, but looking at the fact of various matter, 
including a form of phenol, having been shown to be 
thus absorbed, it appears worth further consideration. 
The action of manure as a preventive falls into the 
Agricultural and chemical department, as the amount 
and nature must vary with circumstances, but it may 
just be observed that in case of farmyard manure being 
applied shortly before sowing it should be covered over 
at once so as to preserve the moisture, and also no dry 
lumps should be left on the surface, as they shelter the 
Flea-beetle. Also, though some amount—and a liberal 
amount—of artificial manure is highly desirable as an 
