22 



every sec9iid evening, ^ of a litre of acid syrup ; and it is wise to £;ive the 

 same treatment to the neighbouring hives. A cure is usually efiected in 

 3 or 4 weeks. If later, it is generally regarded as a sign that the queen is 

 diseased, in which case it would be well to replace her. Occasionally the 

 queens die during the treatment ; but this is not frequent. 



This treatment was very successful in diseased hives belonging to 

 Bertrand (59). All the hives that were treated, were cured. Cowan (60), 

 who has also used Hilbert's treatment with some slight modifications, has 

 had the same success ; and such is his confidence in the treatment that he 

 does not fear to introduce into his apiary foul brood colonies for treatment. 

 Some have found the treatment ineffective ; but Bertrand thinks (59) that 

 in all such cases there has been something la'^king ia the work, some precau- 

 tions overlooked or neglected. 



Experiments on the antiseptic value of salycylie acid. Salycylic acid agar 

 ■was made containing 5 grams of 12J per cent, solntion of salycylic acid ia 

 one litre of agar. Petrie plates were made from this and streaked on the 

 surface with B. alvei. At the same time control cultures on ordinary agar 

 were made. The results were abundant growth on the control plates and 

 good growth, (but somewhat lees than on the control plates) on the salycylic 

 acid agar. 



Salycylic acid Vapour. One gram of the acid was evaporated in our 

 laboratory according to the directions given by Bertrand (59), in a box about 

 the same size as a hive. Agar plates streaked with spores of B. alvei were 

 left in different parts of the box during the fumigation for 10 minutes. 

 The plates were then taken out, the covers put on and the plates incubated 

 at 37°C. for 48 hours. 



Results. Fumigated plates — no growth. 



Control plateE — abundant growth. 



From these experiments it will be seen that the vapour of salycylic acid 

 acts antiseptically, and that the feeding of the acid in the syrup, in thepropor- 

 'tions specified, probably acts as a stimulant to the bees, enabling them to 

 withstand or throw off the disease. 



(3) Camphor. Oasipow (61) was the first to use camphor as a crirative; 

 and Bertrand (59) describes the use of it as follows : " There is," says he, 

 "placed upon the battom board of the hive, enveloped in a piece of muslin, 

 " a piece of camphor about the size of a walnut, which is replaced when it has 

 " evaporated. The presence of the camphor permits the bees to clean out the 

 " cells containing dead larvae and stop the development of the disease. So 

 " long as a hive contains some of the substance foul brood will not develop, 

 ' at least according to our experience and to that of several other beekeepers. 

 " The first thing to do then, when one doubts the state of health of a colony, 

 " is to emplov the Ossipow remedy before proceeding to more radical means. 

 " One can administer o*mphor in food by dissolving it in its own weight of 

 "alcohol." 



Experiments on the antiseptic value of Camphor. Sloped agar in tubes 

 was inoculated with one loopfnl of spores of B. alvei, and a crystal of cam- 

 phor about the size of a large pea was dropped in*o the tube. The tub-is 

 were then capped with tin foil paper and kept at 22''0. and BT^O.; and 

 control cultures were made at the same time. At 22°0., after two days, 

 there was good growth in the camphor tube. At 37°0., after two days, com 

 pared with the control tube, the camphor tube showed slight restriction of 

 growth, the extra heat having evaporated the camphor more quickly. 



Another series was made by esing agar Petri plates streaked with 2 



