120 THE BOOK OF THE LANDED ESTATE. 



to a great depth. The dung of all birds is highly valuable as a 

 manure, and it improves by being kept for some time in the form of 

 compost. In those .parts where guano is found it is mixed up with 

 bones of dead birds and feathers. It is imported into this country at 

 prices averaging from 10 to 13 per ton. The effect of guano on all 

 kinds of crops is very striking, and it must be so from its ingredients, 

 as it contains much of the chief elements wanted in the soil for the 

 food of plants, as will be seen by the following analysis of Peruvian 

 guano : 



Water, .-,/..'. Alt 13.09 



Organic matter containing ammonia, . . 53.17 

 Common salt and sulphate of soda, . . . 4.63 



Carbonate of lime, 4.18 



Phosphate of lime and magnesia, . . . 23.54 

 Silicious matter, or sand, . . . . 1.39 



100.00 



This is, of course, pure guano ; but for many years past farmers have 

 been frequently imposed upon by manure-dealers. They receive certain 

 stuffs called guano, but which are really collections of spurious articles. 

 Sometimes, however, inferior guano is shipped from the guano-beds into 

 this country by respectable dealers without their being aware at the time 

 of the fact. The surface of the guano-bed contains a large quantity of 

 sand, and this must be removed to get at the genuine article ; and even 

 where there is no sand, the surface is always inferior to the underlying 

 portion, as it is exposed and deteriorated by the influence of the weather. 

 It is a great advantage to deal with respectable merchants in the trade, 

 as such men usually take care to have the article properly analysed 

 before offering it for sale. However, from the present demand which 

 there is for guano, there is always an inducement with unprincipled 

 dealers to palm an inferior article on the farmer; and it therefore 

 remains with all those who purchase guano, or indeed any artificial 

 manure, to be certain it is good before purchasing, which can be got 

 by having a written guarantee that it is good and up to an analysis 

 given; and with a little attention to samples of really good guano, 

 any one may come to know a good article on examination. Artificial 

 guanoes and adulterated guano are mixed with gypsum, peat, coal-ashes, 

 burnt earth to give them a light colour, and common salt ; umber is also 

 used extensively in adulterating guano. I have generally been able to 

 test guano in this way : Put it into a glass with water, and stir it up 

 and break any small lumps which may be in it, and then allow the 

 muddy water to run off, when, if the article is good, there should not be 

 any sand or small stones in the bottom, at least these ought to be in a 



