460 THE GARDENER. [Oct. 



most ignorant of the art of forcing through such a season will at once 

 conclude that the production of good Grapes in early spring, in this 

 ever-changing climate, must be one of the most difficult tasks of the 

 horticulturist. Whatever structure it is that insures the greatest pos- 

 sible amount of light, and is at the same time the most easily heated 

 to and maintained at the necessary temperature, must of necessity 

 be the best for early forcing. Very little consideration will serve to 

 convince any one that the form of vinery which presents almost its 

 entire surface of glass to the south, so as to catch every gleam of sun- 

 shine, must be the best. 



The "lean-to" as represented by fig. 6 is beyond all doubt the 

 best for early forcing. Indeed it is a good form for producing Grapes 

 at any season of the year, but especially at the time now under con- 

 sideration. The wood-work should not be any heavier than gives suffi- 

 cient strength, and it should be glazed in large panes with 22-ounce 

 British sheet-glass. The amount of pipes for heating it should not be 

 less than six rows of 4-inch pipes the whole length of the house and 

 round both ends, besides a steaming-tray. The whole of the inside 

 wood-work and back wall should be white, so as to reflect as much 

 light as possible on the tender growths of the Vine. Reference to the 

 engraving shows the arrangement of the drainage and depth of soil 

 as referred to under the head of "Border-making." 



In forcing that has to commence in any of the winter months, there 

 can be no doubt that artificial heat judiciously applied by hot-water 

 pipes to the soil from beneath is a great advantage. In arranging for 

 this the pipes should be immediately over the concrete, and covered 

 over in a shallow chamber by pavement, and the drainage placed over 

 the pavement ; or the pipes may be surrounded with an open or honey- 

 combed brickwork drain, which drain can be connected with similar 

 open drains running right and left among the open rubble, of which 

 the drainage is composed. A border 24 feet wide should have four 

 rows of hot-water pipes running underneath it. 



The ventilation, especially of vineries where early forcing is carried 

 on, is of very great importance. For it is, especially in those days of 

 large panes of glass and close laps, of great importance to keep the air 

 fresh, and constantly renewed. The ingress of cold currents of air is 

 most objectionable. It is of much importance to heat it before it 

 enters the body of the vinery and plays on the tender foliage and fruit. 

 Many ways have been recommended to effect this end ; but the best 

 way is that invented by William Thomson, and illustrated by him in 

 his ' Treatise on the Vine.' * It is termed the " hot-air ventilator," 



* All who require the best and most elaborate information bearing on every- 

 thing connected with Grape-growing, should read Mr Thomson's ' Practical 



