Manurial Properties of Clay from Gas- Works. 305 



that the ammoniacal salts and other compounds of nitrogen pro- 

 moted this luxuriant growth of turnips, and that the sulphur 

 played but a subordinate part. Chemists, unfortunately, lend 

 their authority to the opinion, and assert that soils always contain 

 an abundance of sulphates, and, therefore, farmers need not 

 trouble themselves to add sulphur. But is this so? May not 

 the superior action of dissolved bones, superphosphate, and 

 similar compounds be due in a great measure to the sulphuric 

 acid they contain, and not simply to soluble phosphate which 

 does not enlist in the soil, or insoluble phosphate " in a fine 

 state of division?" I confess myself strongly of opinion that 

 the sulphuric acid is a very potent agent in bringing about the 

 good results which are so familiar from compounds in which it 

 is used, and when we recollect the raising of a crop of turnips by 

 watering the drills with dilute sulphuric acid only, and the other 

 successful experiments collected by Johnston (" Experimental 

 Agriculture," p. 104-5), I cannot help attributing the success 

 with turnips, above described, as much to the sulphur compounds 

 as to the compounds of nitrogen. Does not the known efhcacy 

 of woollen rags as a manure point in the same direction ? I know 

 of course how large a proportion of nitrogen they contain and 

 how this is usually dwelt upon, but is it considered that they 

 contain an amount of sulphur which is capable of forming 

 12^ per cent, of their weight of anhydrous sulphuric acid, and 

 that the hop, for which they are almost a specific, contains a 

 sulphurized oil nearly, if not altogether, similar to the oils of 

 mustard, garlic, onions, &c. ? When nitrogen compounds can 

 be purchased more cheaply than at present, other ingredients of 

 manure may perhaps receive closer attention than they now 

 obtain. The extreme importance, and increasing price of nitro- 

 gen, has pushed it somewhat beyond its true position. 



Cognate with what has been said already of turnips, and of 

 sulphur as an element of their growth, is the question of 

 sulphurized compounds as a manure for grass. Confessedly the 

 first agriculture in the world is that of Britain. The able and 

 impartial testimony of M. Lavergne may well make every farmer 

 proud of the body of which he is a member. But though 

 pre-eminent it is not perfect, and even farmers confess that the 

 state of grass land in England is a reproach which they would 

 gladly wipe away. Hence the struggle on the part of tenants to 

 break up, opposed by (as I think) the wise determination of 

 landlords to retain, permanent grass. But why does the blot 

 exist ? What brought, and what can remove it ? With all 

 the aid which modern enterprise and discovery have rendered 

 the farmer, by placing at his disposal many valuable addi- 

 tions to his home-made manure, it is a fact which needs no 



