72 ANNUAL OF SCIENTIFIC DISCOVERY. 



oxygen, and only 45 litres of nitrogen, that is, oxygen practically 

 pure for industrial purposes. To extract the gases, the authors 

 employ a pump, and they tell us that if again exposed to char- 

 coal, the oxyg'U will be obtained almost pure. There can be no 

 doubt of it. They give no account of the cost of oxygen ; but it 

 is clear that it will be represented chiclly by the cost of the ma- 

 chinery and cost of working it. — Mec. Mag. 



THE SEWAGE QUESTION. 



Among the best of the labored articles upon this subject we 

 have jieruscd is one entitled " A Chemist's view of the Sewage 

 Question," by Edward C. C. Stamford, F.C.S., published in the 

 Cliemical News. IMr. Stamford clearly shows in his essay that the 

 problem cannot be solved upon merely mechanical data. He 

 says: " The present water-closet system, with all its boasted ad- 

 vantages, is the worst that can be generally adopt(?d, briefly be- 

 cause it is a most extravagant method of converting a molehill 

 into a mountain. It merely removes the bulk of our excreta from 

 our houses, to choke our rivers with foul deposits and rot at our 

 iieijxhbors' doors. It increases the death rate, as well as all other 

 rates, and introduces into our houses a most deadly enemy, in 

 the shape of sewer gases." 



Mr. Stamford predicts that tlie water-closet will be ultimately 

 doomed to oblivion. He reviews the process of Mr. Chapman, 

 one of the latest proposed methods of dealing with town sewage, 

 which is In-icfl}' a process of distillation, after treatment with lime 

 and thorough ))utrefaction, points out important defects, and de- 

 cides that its elfeetiveness is to say the least problematical. The 

 process of Mr. Glassford, evaporation with sulphuric acid, he 

 deems far more certain. But both these methods are connected 

 with the water system, and this Mr. Stamford considers a radical 

 defect. 



The dry-earth system of Moule he considers the most hopeful 

 of any yet proposed. The question of removal of sewage is not 

 the only one that is to be considered ; what to do with it after it is 

 removed is the most puzzling part of the problem, and is strictly 

 a chemical question. 



The Moule earth system is the onl}' one that has taken into full 

 account the chemical bearings of the question and has dealt with 

 it in a simple and practical manner. It at once provides for dis- 

 posal and removal, making tlie former the prime object. 



Mr, Stamford, in order to obviate a difliculty which seems to us 

 purely imaginary, namel}', the difliculty of obtaining a sufiicicnt 

 supply of pure dry earth, proposes to substitute seaweed charcoal, 

 a powerful absorbent. 



Kow, .^o far as this is concerned we believe there will ulti- 

 mately l)e no difTieulty in oblaining earth for the purpose, but if 

 the system should become general, the privilege of furnishing 

 earth and taking awa\' the resulting compost will be so valued as 

 to make it a sul)ject of solicitation; perhaps even a commercial 



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