CULTIVATION. 



371 



grown under roofs very different in appearance from 

 the elegant clear glass roofs of the present day* 

 which, nevertheless, necessitates some kind of invention 

 for temporary shading in summer; but it is to be 

 hoped this will be superseded by further improvements. 

 Double glazing is now spoken of as answering the 

 twofold purpose of saving shading and fuel ; but as 

 there appear to be different opinions on its merits, 

 further experience is therefore desirable before it can 

 be safely recommended. 



With regard to watering, it is difficult to explain in 

 words, or lay down a rule, what constitutes the extremes 

 of dry and wet soil in a flower-pot, feeling is perhaps the 

 best guide ; if, on taking a pinch of soil between the 

 finger and thumb, the particles will not adhere, then it 

 is too dry; if it adheres, and falls like a dry wafer, then 

 the plant is not in immediate want of water ; but, on the 

 contrary, should the soil stick to the fingers like a wet 

 wafer, then the whole is in a bad condition, and should 

 the plant be weakly, it will get worse if allowed to 

 remain in the sodden soil; for the correctness of this test 

 care must be taken not to be deceived by the surface- 

 soil, for it may be either dry or wet, and the contrary 

 lower down. Another test of the state of soil is to 

 give the side of the pot a smart tap with a hard piece 

 of wood ; should the sound be hollow, with a little 

 tone, then the ball is dry ; if, on the contrary, there 

 is only the dull sound of the tap, without any tone, 

 then the ball is moist and tight in the pot. To those 

 in the habit of watering the same plants for a length- 

 ened time, this test is of service, but it must not 

 altogether be depended upon. The quality of the 

 water has great effect on the health of the plants. 

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