6 ATMOSPHERIC HEAT OF VINERY. 



ventilator (fig. 5, page 12) is a plan I have devised and 

 used during winter for letting a constant stream of air 



Fig. 4.' 



STEAMING-TRAY. 



The water flows in the direction indicated by the arrow, ascending by the small 

 pipe A into the tray, and by gravitation along the tray from B to C, descend- 

 ing again into main circulation by the other small pipe D. 



into the house, which, before it escapes amongst the 

 foliage of the vines, must of necessity become as hot as 

 the atmosphere of the house. To this mode of admit- 

 ting a constant stream of air previously heated into our 

 early vinery, I attribute to some extent the extra- 

 ordinary fine flavour of early grapes we began to cut 

 on the 1st of January 1862. 



With regard to boilers, I think it unnecessary to say 

 much; their name is legion, and many of them are 

 good. My own observation has led me to prefer those 

 that expose the greatest heat-absorbing surface, not 

 under the fire, or by the side of it, but immediately 

 over it, provided always that their construction is such 

 that every portion of their heat-absorbing surface can 

 be swept clear of soot and ashes daily ; for if these are 

 allowed to gather on the boiler, they will, as non-con- 

 ductors of heat, destroy its heating power to the extent 

 of the surface they cover. Cast-iron boilers, if properly 

 constructed, are as safe, much cheaper, and last double 

 the time of malleable-iron boilers. 



