DIVISION OF CHEMISTRY 103 



SESSIONAL PAPER No. 16 



These ashes are decidely low in potash, the chief fertilizing element in materials 

 of this character. In commercial wood ashes of fair quality, the potash is usually 

 between 5 per cent and 6 per cent. It therefore would seem that these ashes have been 

 partially leached or mixed with a good deal of sand, etc. 



Laboratory No. 1061,8.—' Soft Maple Ashes ' from C. P. M., Sardis, B.C. Sample 

 consists of powder and a number of vitrified masses or clinkers. 



Analysis. 



Per Cent. 



Potash 1919 



Phosphoric acid 2.71 



Lime Cexisting chiefly as carbonate) 35-76 



Mineral matter insoluble in acid 316 



These ashes contain an unusually high percentage of potash and are, in conse- 

 quence, of very considerable fertilizing value. They are practically free from sand 

 or other foreign material and are to be regarded rather as the ' pure ash ' of the maple 

 than as a commercial article. 



Sewage Sludge or Poudrette. 



This sample (Laboratory No. 16273) was submitted to analysis at the request of 

 the Commission of Conservation, it having been obtained from Manchester, England. 



In various systems of sewage purification by precipitation, a product is obtained 

 from the settling vats or reservoirs, which is generally known as sludge. The com- 

 position of this material will, naturally, vary with the concentration of the sewage, 

 the nature and amount of the precipitant (lime, alum, etc.), and the degree to which 

 it is subsequently dried; hence the fertilizing value is a matter of close inquiry. 



Analysis. 



Per Cent 



Moisture 318 



Organic and volatile matter 3306 



Mineral matter 63.76 



lori.oo 



Clay, sand, etc., insoluble in acid 45.12 



Oxide of iron and alumina 9-81 



Lime 2-03 



Phosphoric acid 1-22 



Potash 08 



Nitrogen, in organic matter 1-45 



For the purpose of comparison, analyses of sludge from Hamilton and Toronto, 

 made in the Farm laboratories some years ago, are appended. 



Analyses of Sludge. 



Hamilton. Toronto. 

 Per Cent Per Cent. 



Moisture 3175 3.94 



Organic and volatile matter 390.') 40.91 



Mineral matter 39-20 55.15 



100.00 100.00 



Clay, sand, etc., insoluble in acid 9-66 34.05 



Oxide of iron and alumina 474 13.65 



Lime 9-23 2-07 



Magnesia 10 40 .33 



Phosphoric acid -69 1.24 



Potash -19 -21 



Nitrogen, in organic matter -84 2.04 



