180 MANUAL OF MODERN VITICULTURE. 



obtained remarkable results with it in his vineyard of Haut- 

 Bailly (Gironde). It is obtained by combining ordinary am- 

 monia with copper turnings, or copper oxide, in the presence 

 of air. The blue liquid thus obtained is diluted with water, 

 so as to bring the proportion of copper to 1 or 3 per cent. 

 Its adherence is equal to that of blue water, its qualities are 

 similar, and it has the advantage of never burning the leaves. 

 The high cost alone prevents its general use. 



4th. Mixture of DauphinJe. Masson, Professor at the 

 School of Viticulture of Beaune, and Dr. Patrigeon* proposed 

 hydrocarbonate of copper as a substitute for blue water. It 

 is obtained by the action of carbonate of soda or potash (com- 

 mercial) on sulphate of copper. According to the authors, it 

 has the. following advantages: 



1st. The carbonates are much cheaper than liquid ammonia,. 



2nd, The liquid resulting from their combination with 

 sulphate of copper is easier to handle than blue water. 



3rd. The greenish white, or greenish-blue spots left on the 

 leaves allow the proprietor of a vineyard to check the work 

 done by his workmen. 



4th. The colloidal precipitate of hydrocarbonate of copper 

 is very adherent to the leaves, and plays the same part as 

 the hydrate precipitate of blue water. 



5th. This precipitate remains a long time in suspension 

 in the liquid, and does not choke the machines. 



6th. . There is no formation of acid sulphate liable to burn 

 the leaves, as in the case of blue water, the acid remaining 

 constantly neutralized. 



Masson gives the following practical formula for preparing 

 this mixture : 



Water ... ... ... 100 parts 



Sulphate of copper ... ... 1 // 



Carbonate of soda ... ... 2 n 



If the copper percentage is increased the quantity of car- 

 bonate of soda should be increased in the same proportion. 

 Dr. Patrigeon uses the following mixture: 



Sulphate of copper ... ... ... 4 parts 



Carbonate of soda (commercial)... ... 6 n 



Water ... 100 



The mixture of Dauphinee has given good results wherever 

 it has been properly applied. It has more adherence than 

 the Bordeaux mixture, but is rather more expensive. 



* Dr. J. P. G. P*tiigeon, Le Mildiou, peronospora viticola, Puris, 1887. [Transls.] 



