REPORT OF THE CHEMIST. 153 



by artilicial lieat is expensive aud is liable to the objection agamst solar 

 evaporation. This, however, may be obviated by conductiug the evapo- 

 ration iu closed vessels and passing the vapor through a deodorizing 

 solution, or, what would be, perhaps, cheaper and equally effectual, 

 passing it into the furnace. 



There remains, however, a formidable objection to artificial desiccation 

 of sewage — the enormous cost of evaporating 2,000 cubic feet of water 

 daily, to recover, in an available form, the valuable material in the wastes 

 of a^ city of 100,000 inhabitants. But no cheaper method has been de- 

 vised which will at once accomplish the two objects, to wit : Economizing 

 what is valuable in the sewage and securing the health and comfort of 

 the inhabitants. 



The practicability of this method of disposing of sewage, aud Bcono- 

 niiziug, in a form capable of being transported to a distance, all that is 

 valuable in it, has never been fully tested by actual experiment undei 

 the guide of science. A company, with a capital of £500,000, has lately 

 been formed in England for the purpose of submitting this question to 

 a i)ractical test. The company has secured the services of William 

 Hope, esq., as engineer, and Professor J. T. Way, as consulting 

 chemist. These names afford a guarantee that the experiment will be 

 faithfully made in strict accordance with the principles of science. Even 

 though the cities may be required to pay a heavy bonus to carry out a 

 system of thorough cleansing that will secure to them health and com- 

 fort, and at the same time contribute to maintain the productiveness of 

 the soil from which they are fed, they can well afford to bear the burden. 

 The present imperfect system costs the city of Paris 9,000,000 francs 

 annually, while the products of the waste matter are worth but 10 per 

 cent, of that sum. A perfect system, could one be devised, would hardly 

 be more expensive. Other cities fare no better than Paris ; many of them 

 not so well. 



How deeply the importance of this subject is felt in the more advanced 

 circles of our civilization is indicated in a remark made by the managers 

 of the Vienna Exhibition for 1873. In their announcement of special 

 l^rogrammes they say : 



How enlarged we find tlie amount of the useful material and tlie means of satisfying 

 our requirements, by a retrospective view of the last ten or twenty years only ! It suffi- 

 ces to single out from the list of substances, the value of which has been thus increased, 

 one more, much despised, material, viz, human excrements. Without contradiction, 

 these are considered as some of the most disgusting wastes ; nevertheless China and 

 Japan mainly owe their flourishing agriculture to the extensive use made of them, and 

 one of the greatest chemists of our own time^ Baron Liebig, has acknowledged that 

 they contain the means of restoring to the soil of Europe its power of production, a 

 loower which wiU soon be exhausted otherwise. 



Considering this, is it not to be called one of the greatest absurdities to spend mill- 

 ions in getting rid of a substance which would, if we made. proi)er use of it, make us, 

 by several millions, richer? 



Thus we see the magnitude and weight of this subject is commanding 

 the attention of agricultural chemists, of sanitary philanthropists, of 

 political economists, and should, in its broader reaches, address itself to 

 the statesman who would explore the causes of national decay and ruin. 



By way of recapitulation, we present this subject condensed into a 

 few maxims: 



1. The measure of a nation's prosperity, and the security of its pro- 

 longed existence, are involved in its capacity to produce human food and 

 clothing from its own soil. 



2. The capacity to produce food and clothing can be made permanent 

 only by a strict observance of tfiat law of vegetable chemistry which 



