N. MATERIA MEDICA, THERAPEUTICS, AND HYGIEXE.577 



give this system a trial in this country, they would find it 

 worth adoption. 1 A, December 8, 1871, 277. 



SCOTT PROCESS OF UTILIZING SEWAGE. 



A new feature has lately arisen in connection with the ques- 

 tion of the disposal of sewage, a problem that has been so 

 difficult of solution in most parts of the world. This consists 

 in a process invented and patented by Major General Scott, 

 of England, for making from sewage dissolved in water a ce- 

 ment equal to the best Portland cement, or an excellent hy- 

 draulic lime. The cost of this does not exceed that of Port- 

 land cement prepared in the usual manner, and the offensive 

 nature of the fcecal matter is completely destroyed. The 

 principle of the process consists in mixing with the sewage 

 quantities of lime and clay, the former ingredient combining 

 with the carbonic acid of the fcecal matter to form carbonate 

 of lime, which is precipitated with the other solid ingredients 

 in the form of an impalpable powder. The lime and clay 

 are preferably thrown into the main sewer some little dis- 

 tance before the outlet, so as to insure a more complete in- 

 corporation of the different matters, while, at the same time, 

 destroying the slimy, glutinous character of the sewage, 

 " sludge," and keeping the drain free from the festering and 

 putrefying deposit which otherwise tends to choke it. The 

 clay and the lime do not merely facilitate the deposition of 

 solid matter, but, as is well known, they tend to purify the 

 supernatant water. As lime and clay are the chief constitu- 

 ents of those limestones which, on calcination, yield the best 

 hydraulic limes and cements, it is claimed for this process that 

 there is a sufficient gain of cement-making material abstract- 

 ed from the sewage to make the operation profitable, inde- 

 pendently of the advantages secured by thus deodorizing and 

 defecating the excrementitious matters of towns, which must 

 otherwise be disposed of in a manner more or less prejudicial 

 to health, and very often at great expense. 



The success of the new process depends in no small degree 

 on the fact that the precipitated matter supplies to a consid- 

 erable extent the fuel necessary for the burning operation. 

 The sewage being allowed to settle in tanks and the super- 

 natant water drawn off*, it is found to be deodorized, and may 

 be exposed to the drying action of the air for an indefinite 



Be 



