550 EFFECT OF AMMONIACAL MANURE. 



arid damp, rub upon the heated pipes, the flues, or a hot piece of metal, 

 a small piece of carbonate of ammonia with some water (not dry) j the 

 peculiar smell of smelling salts will be instantly perceived, and if this 

 is done at the two ends of a house, as well as in the middle, the air 

 will rapidly receive a sufficient charge of the substance. After it has 

 been allowed to remain about the plants for a short time, some gardeners 

 syringe their houses freely ; but it is doubtful whether that is the best 

 plan, provided the air of the house is naturally damp. The effect of 

 this simple application is very remarkable, quickly producing a visible 

 change for the better in the appearance of the plants. 



But caution must be used in the application. A piece of carbonate 

 of ammonia as large as a shilling is sufficient for one charge in a stove 

 40 feet long ; and it is indispensable that it should be volatilised by 

 rubbing it in water, otherwise its causticity is too great, and leaves are 

 burnt. 



It is no doubt owing to the quantity of carbonate of ammonia 

 which they evolve, that " dung-linings " have been foimd so much 

 more conducive to healthy vegetation, than heating materials of any 

 other kind. An experienced gardener gives the following directions 

 for employing it in Cucumber pit^ heated by hot water : — Use it twice 

 a week, in the following manner. When you close the pit for the 

 night, place a bit of the carbonate (pure), about the size of a large 

 garden Pea, alternately back and front, under each light, on a small 

 piece of glass, but dip the glass first in water, to wet it. The surface 

 of the soU and interior of the pit should also be slightly syringed or 

 otherwise moistened, in order that a quantity of moisture or vapour 

 may be formed in the atmosphere at the time of the application ; then 

 shut up close for the night. The only caution required is to take care 

 to procure pure carbonate of ammonia, and to use it only in a moist 

 atmosphere, for it is much more caustic in dry than in moist air. 



The effect of ammoniaoal manure is to promote the growth 

 of all the green parts, the colour of which becomes rapidly 

 more intense under its influence. In excess it causes rank- 

 ness, that is to say, it forces the vegetable tissue to form faster 

 than it can consolidate, and in such a state plants are pecu- 

 liarly subject to the attack of mildew. It is weU known among 

 farmers that rank corn is certain to mildew; rank potatoes 

 suffer more from the same cause than such as form slowly; 

 and the fact has been also observed in the case of the Vine 

 disease. Whether the presence of nitrogen in excess is pecu- 

 liarly favourable to the development of all kinds of fungi, 

 which is probable, or whether they merely attack rank plants 



