296 GREEN-HOUSEOBSERVATIONS. 



Cape bulbs should be placed near the glass, and free from 

 the shade of other plants. Cleanliness through the whole 

 house and among the plants ought at all times to be at- 

 tended to. 



DECEMBER. 



THE weather may probably be now severe, and it is at 

 all times advisable to keep the temperature as steady and 

 regular as possible. The thermometer should be kept in 

 the centre of the house, and free from the effects of reflec- 

 tion. As noticed last month, sun heat may be as high as 

 50 in the house, and would not be hurtful, but it should 

 not continue so for any considerable time without admis- 

 sion of air. The fire heat should not exceed 45, and never 

 below 35. It ought not to continue at that point 36 is 

 the lowest for a continuation that with safety can be prac- 

 tised, and where a collection of Cactii are kept, 40 should 

 be the lowest. So that no error may occur, the tempera- 

 ture ought to be known in the coolest and warmest parts 

 of the house, and the variation remembered ; then what- 

 ever part of the house the thermometer is placed, a true 

 calculation of the heat of the whole interior can be made. 

 We would recommend to the inexperienced to keep the 

 thermometer in the coldest part of the house. A green- 

 house compactly and closely built, and the lowest row of 

 top sash all covered with shutters, (which no house ought 

 to be constructed without,) will seldom require artificial 

 heat ; but by being long kept close, the damp will increase. 

 In such case give a little fire heat, and admit air to purify 

 the house. In fresh mild weather give liberal portions of 

 air all over the house ; and though there is a little frost, 

 while mild, and the sun shining, the plants will be bene- 

 fited by a small portion of air for the space of an hour, or 

 even for half of that time. . 



Whatever state the weather may be through the winter, 

 never keep the house long shut up. Thirty-six hours 



