A Method of hastening the Maturation of Grapes, 33 



exposed alburnum might be again covered with new bark by 

 the end of autumn, the removed circles were made rather 

 less than a quarter of an inch in width. Two vines of the 

 white Frontiniac, in similar states of growth, being trained 

 near to each other on a south wall, were selected for trial ; 

 one of these was experimented on (if I may use the term), 

 the other was left in its natural state, to form a standard of 

 comparison. When the circle of bark had been removed 

 about a fortnight, the berries on the experimented tree be- 

 gan evidently to swell faster than those on the other, and 

 by the beginning of September showed indications of ap- 

 proaching ripeness, while the fruit of the unexperimented 

 tree continued green and small. In the beginning of Octo- 

 ber, the fruit on the tree that had the bark removed from it 

 was quite ripe, the other only just began to show a dispo- 

 sition to ripen, for the bunches were shortly afterwards de- 

 stroyed by the autumnal frosts. In every case in which, 

 circles of bark were removed, I invariably found that the 

 fruit not only ripened earlier, but the "berries were consi- 

 derably larger than usual, and more highly flavoured. 



The effects thus produced, I can account for only, by 

 adopting Mr. Knight's theory of the downward circulation 

 of the sap, the truth of which these experiments, in my 

 opinion, tend strongly to confirm. I therefore imagine by 

 cutting through the cortex and liber without wounding the 

 alburnum, that the descent of that portion of the sap which 

 has undergone preparation in the leaf is obstructed and con- 

 fined in the branches situated above the incision ; conse- 

 quently the fruit is better nourished and its maturation hast- 

 ened. It is certainly a considerable point gained in the cul- 

 ture of the vine, to be able to bring the fruit to perfection, 

 by a process so simple, and so easily performed. But lest 

 there should be any misconception in the foregoing state- 

 ment, I will briefly describe the exact method to be follow- 

 ed by any person who may be desirous of trying this mode 

 of ripening grapes. The best time for performing the ope- 

 ration on vines growing in the open air, is towards the end 

 of July, or beginning of August ± and it is a material point, 



Vol. 33. No. 129. Jan. 1809. C not 



