APPENDIX. 125 



sulphur strewed over the slates till near the ripening 

 season, that no inconvenience need be apprehended. 

 It will be perceived that the ventilation is all lateral, 

 and, on the same principle as that of my orchard- 

 houses, nothing can be more perfect. In the figure it 

 will be seen I have left a small aperture under the 

 apex of the roof for the escape of rarefied air. In 

 very hot weather this may be useful, but in my slate- 

 floored ground vineries I have not done this, and yet 

 the ventilation is perfect. I have not yet ascertained 

 in what manner the heated air escapes. The venti- 

 lating apertures are all on the surface of the soil, and 

 at the same level ; but I suppose it stoops to get out, 

 having no other mode of egress. 



DIMENSIONS OF GROUND VINERIES. 

 2fo. 1, for a single vine in centre. 



Width at base 30 inches. 



Slope of roof . . . . .20 inches. 

 Depth in centre . . . .16 inches. 



No. 2, for two vines 14 iiicJies apart. 



"Width at base 42 inches. 



Slope of roof . . . . .28 inches. 



Depth in centre . . . .20 inches. 



These dimensions need not be arbitrary, for ground 

 vineries of larger dimensions may be made with every 

 chance of success, and Hamburgh grapes grown in 

 Bedfordshire instead of cucumbers; for no part of 

 England can be more favorable to grape culture than 

 the fertile, sandy districts of a portion of that county. 

 We have heard of forty acres of cucumbers being 

 grown for pickling, and one day we may hear of forty 



