52 



CULTURE OF THE GRAPE. 



rows being eighteen inches, the width of the tank, and the 

 rows being a foot apart ; so that each joint of slate shall 

 have the support of brick under- 

 neath. Lay the slate upon the brick 

 piers, and cement the joints with ut- 

 most care, using the best New-Jer- 

 sey cement, mixed with an equal 

 quantity of pure sand. Fig. 8 shows 

 the appearance of the work at this 

 stage. The outer lines indicate the 

 sides of the house ; the lines in the 

 centre indicate the walk; and the 

 checked belt the course of slate, con- 

 stituting the bottom of the tank. 

 As the under surface is exposed to the air, except the 

 small part which rests upon the brick at the joints, heat 

 is given off at the bottom of the tank as well as at the 

 top ; which is a great advantage over Mr. Hooker's plan. 

 For the sides of the tank, lay a single brick edgewise. 

 This will give a depth of three inches for the water, 

 which is quite sufficient. Bed the brick carefully in 

 Cement, and also cover the inside face. The top course 

 of slate should be laid and cemented with as much care 

 as the bottom, in order to prevent any escape of steam. 



