vertue meaning in English

弗图

I contented my self with these discoveries for this time , and came back musing with myself what course i might take to know the vertue and goodness of any of the fruits or plants which i should discover ; but could bring it to no conclusion ; for in short , i had made so little observation while i wad in the brasils , that i knew little of the plants in the field , at least very little that might serve me to any purpose now in my distress
我记得，在伯尔伯里上岸时，几个在那儿当奴隶的英国人因葡萄吃得太多，害痢疾和热病死了。但是，我还是想出了一个很好的方法利用这些葡萄，就是把他们放在太阳下晒干，制成葡萄干收藏起来。我相信葡萄干是很好吃的在不是葡萄成熟的季节，就可以吃葡萄干，又富营养又好吃。