I860.] 



THE SOUTHERN PLANTER. 



651 



AFRICAN GUANO. 





Best 



In- 



Low 



Ichaboe. 



ferior. 



quality. 



Ammoniacal matter. .45 





20 





21 



17 



Fixed alkaline salts. .12 



16 



U 



Rock, sand, earth. ... 1 



3 



25 



Water 22 



32 



24 



100 



100 



100 



The guano from the islands on the British 

 coasts, contains the same ingredients, but 

 the soluble salts are generally washed out 

 by the action of rain. The following is the 

 analysis, by Dr. R. D. Thomson, of guano 



gathered on Ailsa Craig: — 



Water 50.30 



Organic matter and ammoniacal salts, 



containing 3.47 per cent, ammonia .. . 12.50 



Phosphates of lime and magnesia 12.10 



Oxalate of lime 1.50 



Sulphate* and phosphate of potash, and 



chloride of potassium 1.00 



Earthy matter and sand 15.00 



Simple Manures supply only one or two 

 of the materials required for the growth and 

 nourishment of plants. The ammoniacal 

 liquor of gas-icorJcs, in a very diluted state, 

 has been advantageously applied to the soil, 

 on account of the nitrogen which it supplies. 

 JSoot has also been used, from furnishing 

 salts of ammonia. Nitrates of potash and 

 soda have been recommended not only on 

 account of the alkalies, but also on account 

 of the nitrogen which they contain in 

 the form of nitric acids. The quantity 

 of gluten is said to be increased by the use 

 of nitrates. Carbonate of potash and soda 

 and chloride of sodium, are frequently used 

 as manures. The latter is especially useful 

 in the case of plants cultivated inland, as 

 Cabbages, Asparagus, and Sea-kale. As 

 lime is found in all plants, the salts contain- 

 ing it are of great importance. It may be 

 used in the caustic state, with the view of 

 decomposing vegetable matter, and aiding 

 in the formation of carbonic acid. It also 

 neutralizes any acid previously in the soil, 

 and is said to occur occasionally in boggy 

 and marshy land, abounding in species of 

 Juncus, Carex, and Eriophorum, with some 

 Calluna vulgaris. Lime also combines with 

 certain elements of the soil, and sets potash 

 free, which reacts on the silica, and renders 

 it soluble. Lime is sometimes washed down 

 into the subsoil; and, in such cases, trench- 

 ing improves the land. Phosphate of lime 

 is a valuable manure, both on account of the 

 lime, and of the phosphorus which it con- 



tains. Whithout the presence of phosphates, 

 gluten, and the proteine compounds of plants, 

 cannot be formed. Phosphate of lime ex- 

 ists abundantly in animal tissues; and hence 

 it must be furnished by plants The use of 

 bone-dust as a manure, depends in a great 

 measure on the phosphate of lime ^which it 

 contains. Besides phosphate of lime, bones 

 contain about 3 per cent, of phosphate of 

 magnesia, carbonate of lime, and salts of 

 soda. The gelatine of bones also seems to 

 act beneficially, by forming carbonic acid 

 and ammonia. Bones are best applied mixed 

 with sulphuric acid,* so as to give rise to 

 the formation of soluable phosphates by 

 decomposition. They are broken into pieces, 

 and mixed with half their weight of boiling 

 water, and then with half their weight of 

 sulphuric acid. The mixture is applied to 

 the soil, either in a dry state by the drill, 

 with saw-dust and charcoal added, or in a 

 liquid state, diluted with 100 to 200 waters. 

 Phosphates and other inorganic matters, 

 sometimes exist potentially in the soil, but 

 in a dormant state, requiring the addition of 

 something to render them soluble. Allow- 

 ing the ground to lie fallow, and stirring and 

 pulverizing it, are methods by which air 

 and moisture are admitted, and time is 

 allowed for the decomposition of the ma- 

 terials, which are thus rendered available 

 for plants. Sulphur exists in considerable 

 quantity in some plants, as Crucifera), and 

 it forms an element in albumen; hence the 

 use of sulphuric acid and of sulphates in 

 manures. Sulphate of lime or gypsum, is 

 well fitted as a manure for clover. It acts 

 in supplying sulphur and lime, and in ab- 

 sorbing ammonia. Charcoal in a solid state, 

 has been applied with advantage as a ma- 

 nure. It acts partly by taking up ammonia 

 in large quantities, and partly in combining 

 slowly with oxygen, so as to form carbonic 

 acid. The effects of carbonic acid on vege- 

 tation are said to be remarkably conspicuous 

 in some volcanic countries, in which this 

 gas is evolved from the bottom of lakes. 

 When it accumulates in large quantities, 

 however, it destroys plants as well as ani- 

 mals. 



Manuring with Green Crops is some- 

 times practised. The mode adopted is to 

 sow certain green crops, the roots of which 



* Putrefaction is preferable. See Tyson's re- 

 port, page 360, June number Southern Planter. — 

 [Editor. 



