72 Royal Society. 



tion at 800,000 pipes, and the total number of vines in the country 

 at 800,000,000. 



If Flour of Sulphur be used, the leaves, branches and shoots are 

 first moistened as equally as possible with a syringe ; then the 

 whole is dusted with sulphur, which adheres to the moistened 

 surface. 



This operation would have to be repeated thrice, and would con- 

 sume two ounces of sulphur for every vine, in each of the operations, 

 making a total of 480,000,000 ounces, or about 13,392 tons for the 

 treatment of the 80,000,000 vines in the Alto-Douro, and 133,920 

 'ons for the vines of the whole country. 



Sulphur would not cost less than 10/. per ton, delivered in the 

 centre of the Alto-Douro districts, or in any other part of the inte- 

 rior of Portugal . The expense of sulphur required for the Douro 

 would be 133,920/., and for the whole country 1,339,200/. 



One man could moisten one vine in one minute, and another man 

 could dust it with sulphur in the same time, so that two men could 

 perform the complete operation on about 700 vines daily, at a cost 

 of Is. 3d. each man for labour, making a total of 14,285/. in the 

 Alto-Douro, and 142,850/. for all Portugal. 



I will suppose that there are 4000 vineyards in the Alto-Douro, 

 planted each with 20,000 vines. The first cost of syringes and 

 fumigators would amount to not less than 10/. for each vineyard, or 

 a total of 40,000/. for the Alto-Douro. 



One quart of water would be required for every vine in each ope- 

 ration, making a total of about 90,000 pipes, the cartage of which, 

 and the labour of distributing it over the mountain vineyards, in 

 tubs, on men's heads, would cost a minimum of 10s. per pipe, or a 

 total of 45,000/. for the Alto-Douro, and 450,000/. for the whole 

 country. . 



Recapitulation. 



In the Douro. In the whole 



country. 



For sulphur, say £135,000 £1,350,000 



For labour, at £15,000 for each of the 



three operations 



For water, at £45,000 for each of the "1 



three operations, or as much as the > 135,000 1,350,000 



sulphur J 



For instruments 40,000 400,000 



£355,000 £3,550,000 



| 



This is independent of any charge for factors or superintendents, or 

 for the extra expense in treating vines and vineyards which are so 

 much further apart than are those in the Alto-Douro. 



This expense to be incurred in the endeavour to save one year's 

 crop, would be equal to a charge of 4/. 10s. per pipe, or to a year 

 and a half's rental of the vineyards, or to more than the whole revenue 

 of Portugal for an entire year. 





