CHAP. H.] FORMATION OF HOTBEDS. 27 



posed to the action of the air; because if the 

 manure is exposed to the action of water and 

 not to air, an intermediate change takes place 

 between putrefaction and decay, to which Pro- 

 fessor Solly gives the term mouldering, but which 

 is, in fact, analogous to that which takes place 

 in vegetable matters when they become changed 

 into peat, and during which the elements of 

 which they are composed are prevented from 

 flying off and forming new combinations, and 

 are thus quite useless as vegetable food, the 

 manure being changed into a black slimy mass, 

 totally unavailable for any purposes of cultiva- 

 tion. This change often takes place in the gar- 

 dens of small suburban houses which are badly 

 drained, and yet constantly watered; and which, 

 being over manured with stable dung imperfectly 

 decayed, have their soil changed into the black 

 slimy substance that I have before described, 

 which is quite incapable of maintaining vegeta- 

 ble life. The soil in flower pots is often found in 

 this state, from frequent watering, and suffering 

 the water to remain in a stagnant condition in 

 the saucers. 



Formation of Hotbeds. — Though several 

 kinds of manure may be used occasionally for 

 hotbeds, the only materials in common use in 

 gardens are, stable manure, dead leaves, and 

 tan. The first of these, which is by far the 

 most general, consists partly of horse-dung, and 

 partly of what gardeners call long litter, that 

 is, straw moistened and discoloured, but not 

 thoroughly decayed. The manure is generally 

 in this state when it is purchased, or taken 



