284 INSECTICIDES, FUNGICIDES, AND WEED KILLERS. 



as being more adherent. Other observers declare the contrary, but it 

 has been generally observed that Ferret's bouillie communicates a 

 greener tint to the foliage and a more prolonged one than other 

 bouillies. Galloway advocates adding to bouillie bourguignonne a 

 certain dose of sugar, and has used with success a mixture of blue 

 vitriol 3 lb., soda crystals 3^ lb., molasses 3 lb. in 10 gallons of 

 water. Whilst causing burns on the leaves of the vine this bouillie, 

 used against black rot, brought the percentage of sound grapes from 

 46 per cent on the untreated vines to 98-51 per cent. For a sucrated 

 bouillie not to cause burns, the amounts of sugar indicated by Ferret 

 and by Earth should not be appreciably exceeded, for with larger 

 doses of sugar the whole of the copper is transformed into soluble 

 cupric saccharate which behaves like solutions of copper acetate. 

 Bee-keepers have protested against the use of Ferret's bouillie, under 

 the pretext that bees by collecting copper saccharate on the surface of 

 the treated leaves are poisoned, and may convey into the honey an 

 element injurious to human health. It took long and careful experi- 

 ments by E. Jacky in 1900 to prove the want of foundation of their 

 complaints, and to demonstrate that if bees are very fond of sugar 

 and molasses, they shun and do not absorb these sweets when they 

 contain copper. 



Use. — After a general infatuation for Ferret's bouillie, at the time 

 when Michel Ferret recommended it as a substitute for bouillie borde- 

 laise, which then possessed many defects, this preparation fell into 

 oblivion. The chief reason, as pointed out by Dr. Cazeneuve, is that 

 the composition of the bouillie bordelaise has been so modified that as 

 far as its action is concerned it cannot be compared with the primitive 

 bouillie. By substituting molasses for sugar and by greatly increasing 

 the dose. Ferret's bouillie has been converted into a solution of cupric 

 saccharate. As this bouillie contains large quantities of soluble copper, 

 its contact with the plant becomes deadly to it. Its adherence is less 

 and it does not stand rain. Ferret's bouillie may be used in all cases 

 where bouillie bordelaise gives good results. However, Barth found 

 it superior in the struggle against mildew. Nijpels found it better 

 against Phytophthora infestans, DeBy., when applied in two sprayings 

 annually. Sorauer prefers it against Asterovia radiosiini, Fr., of the 

 rose-bush and to prevent the fall of the leaves of this shrub, due to 

 the parasiticism of a rust known as Phragmidium subcorticum, Wint. 



Against Alternaria Brassicce f. nigresceiis, Fegl. (I'oasting of the 

 leaves of the melon) it is better than bouillie l)ordelaise and it appears 

 to act on Botrytis cinerea, Fers. [Sderotina Fuckeliana, De By.] (grey 

 rot of the vine) (Nijpels). 



I02b. Various Bouillies. — As soon as the active principle of the 

 cupric bouillies was definitively established efforts were made to fix the 

 cupric hydrate and copper carbonate which they contain in a more 

 durable manner on the leaves. Everything which cements and binds 

 was incorporated therein, milk, albumen, glue, soaps, oils, and resins. 

 However, the action of these binders on copper derivatives is not, 

 as may be supposed, purely mechanical. These substances often act 

 chemically. Most of them form insoluble derivatives with copper, 



