294 WINDOW GARDENING. [CHAP. XL 



impervious to the air. Sometimes the soil in a 

 pot looks black from over-watering ; and when 

 this is the case, the plant should be turned out 

 of the pot, and the black sodden earth shaken 

 off the roots, which should be cut in, and should 

 have all their decayed parts removed. A clean 

 dry pot should then be procured, of the same, 

 or nearly the same, size as the one the plant 

 was taken from, and a quantity of potsherds 

 (old pots broken into small pieces) having been 

 put in so as to fill about a quarter of the pot, 

 it should be filled up with a compost of vege- 

 table mould, sand, and peat, mixed with lumps 

 of charcoal. Thus treated, and only moderately, 

 but regularly, watered with warm water, which 

 should never be allowed to stand in the saucer, 

 the plant will soon recover: and, if judiciously 

 pruned, should the stem have been elongated, 

 it will become handsome, and what gardeners 

 call well grown. 



Rough potting. — The advantage of admitting 

 air in small quantities to the roots of plants no 

 sooner began to be understood, than plans were 

 devised for mixing various substances with the 

 soil, so as to prevent it caking together. The 

 first person who practised this system to any 

 extent was the late Mr. M'Nab of Edinburgh, 

 who mixed large pebbles with the soil with 

 which he potted his heaths, and his plan was 

 attended with decided success. Many years 

 afterwards, Mr. Barnes, gardener to Lady 

 Rolle at Bicton, in Devonshire, introduced a 

 system of potting plants in a soil composed of 

 chopped turf, sand, and charcoal. This system, 

 which he called rough potting, was found to 



