428 CULTURE OF THE PINE- APPLE. 



Ventilation on a larger scale, to control and regulate temperature, 

 should be provided at the highest point of the house. This provision 

 should be ample, and readily controlled, so as to regulate the heating 

 power of the sun with the utmost facility. During the last or fruiting 

 stages, the flavour of the fruit is improved by thorough ventilation. 

 At other times, unless on the sultriest days, it will be seldom or never 

 desirable to open top and bottom ventilators at once. We would 

 recommend, however, a reversal of the usual order. During the 

 coldest weather give air only in front, and not only at the back. 



Shading. Closely allied to ventilation is the question of shading. In 

 the olden times pines were shaded to excess. Possibly that was the dark 

 penalty paid for disrooting. With the glare of light on large sheets of 

 glass and sashless roofs, some have gone to the opposite extreme, and 

 cried " shade not at all." Of two evils, however, it is wise to choose 

 the least. In this case we must elect either to shade or burn. For an 

 hour on each side of noon it will mostly be useful to break the full 

 force of the sun with thin bunting or matting, or have the leaves of 

 free-growing pines browned or scorched. There is indeed another 

 alternative, the placing of the plants a good way from the glass. Early 

 ventilation, so as to dry the leaves before the sun shines upon them, is 

 likewise a preventive of burning. Still, with all these precautions, 

 slight shading may be necessary for a few hours, for the four hottest 

 months in the year ; the less shading, however, the better. 



Temperature. A few general remarks have already been made upon 

 this subject. We propose here giving the temperature of the air at 

 Calcutta, where pines are grown and gathered all the year round, 

 though the heaviest fruit may be said to ripen from April to Sep- 

 tember. The following are average temperatures, and the extremes 

 range from 53 to 129 : 



Temperature at Calcutta. 



Maximum. Minimum. 



January 84-5 60 



February 90 65 



March 90-5 71 



April 97 77-5 



May 95 78'5 



June 91-5 81 



July 88 80 



August 87 80 



September 90 80 



October 91 75 



November 85'5 64 



December 81-5 57 



The following are the night temperatures recommended by Mr. 

 Glendinning : 



