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Towards the end of April 1854, much rain fell in the district; 

 the easterly winds destroyed the young branches ; and in the most 

 exposed situations and heavy soils the O'idium again made its ap- 

 pearance. 



In 1853, the disease attacked the vines bodily, and almost simul- 

 taneously : whereas, in 1854, the O'idium appears to be creeping 

 out of the skin of the last year's wood, and insidiously to extend 

 itself over the branches. 



The globules (to which allusion has been made above) cover the 

 young shoots. I have been familiar with these for twenty-three 

 years past, and the Douro farmers call them the " perspiration" of 

 the vine. They do not indicate disease, whereas the smallest 

 possible quantity of ihepo' branco, or white powder, being transferred 

 to a perfectly healthy vine, immediately infected it. 



In the Alto-Douro the oranges, lemons, citrons and limes have 

 all been blighted, and every kind of vegetable appears to be suffer- 

 ing from sickness. 



The vines which suffered most in the Alto-Douro, in 1853, were 

 the Muscatel, Malvazia, Alvarilhao, Ferral, Agadanho and Senzao. 



Since my arrival in this country I have noticed that the vines 

 grown on walls in the open air, vines grown in greenhouses, vines 

 grown in hot-houses, vines forced, all show identically the same 

 effects of the Oidium of last year, as exist on the vines in the Alto- 

 Douro. 



Taking into consideration all the circumstances above narrated, 

 I have come to the conclusion, 



That the O'idium is the cause, and not the effect of the disease ; that 

 the inclemency of the season m 1853, by checking the circulation 

 of the sap in the vines, produced a predisposition for disease ; that 

 if the O'idium continues to appear on the branches of the vines, it 

 is only too probable that it may in a very few years be destroyed ; 

 that the globules are a sign of health and not of disease, and have no 

 connexion whatever with the fungus called O'idium ; and that if the 

 germ of the Oidium, probably still lurking on the old branches, can 

 be destroyed in the open air as effectually as it appears to have been 

 destroyed under glass, then I feel persuaded that all the vines in the 

 Port- wine districts of the Alto-Douro may be saved. 



