18 



SCIENCE OF GARDENING. 



fermenting, that less of the ammonia which they contain 

 may be lost. 



Guano is the dung of birds, obtained from those portions 

 of sea-coast, whether in South America or Africa, where 

 particular species abound and congregate, and where 

 the dung has been deposited and accumulating for ages. 

 It is, when obtained pure, an excellent but expensive 

 manure for a single crop, and may be applied broadcast 

 at the time of putting in the crop, or sown along the drills 

 with the seeds or sets, or put on just as the crop is coming 

 through the ground. The last is generally the most 

 economical process, and the ground should be hoed over 

 a few days after it is finished. 



Bone-dust is one of the best manures for firm soils, that 

 are not deficient in depth, and it has the merit of being 

 clean, and readily applied. It also lasts a considerable 

 time. Crushed bones, which are in larger pieces, will be 

 even more durable, and are very effective in facilitating 

 drainage. 



Liquid manures are exceedingly useful on a small scale, 

 and especially in pot-culture. They may consist of urine 

 largely dUuted, or the soaking of a dunghill less freely 

 reduced, or a mixture of a good handful of guano wdth a 

 couple of gallons of water, or any of the same processes 

 extended to the required quantity. They can be applied 

 safely to groAving crops, and will produce a speedier and a 

 more marked effect than other manures, because the nutri- 

 tive matter is already in a state of solution. A great deal 

 may be done in this way in small gardens. 



More artificial manures will contain, generally, some 

 solution of the alkalies, (soda, potash, or ammonia,) satu- 

 rating any neutral substance, to render them of convenient 

 application ; or they may be of a more compound nature. 

 As a rule, these three elements, being those upon which 

 plants are more largely nourished, will form the most 

 certain bases for manures. 



The properties of manures are to stimulate and excite 

 the system of plants into stronger and more luxuriant 

 growth, and, in general, if but moderately employed, to 

 increase their productiveness. Great caution is, however, 

 necessary in adapting the quantity and quality to the 



