20 WILLIAM M. HAMLET. 



sufficient it will be if I say that town inhabitants : — (1) Used the 

 street as a sewer ; (2) Advanced to the cespoo] system, the use of 

 pans, tubs, et hoc genus omne; (3) Invented the water-carriage 

 method of removal with discharge into rivers and seas. But a new 

 danger arises from the mixing with water and removal to a 

 distance, man is confronted with new dangers and new diseases — 

 sewer disease, and the next question is, what is he to do with it ? 

 how dispose of it having in view two things : the health of the 

 state, and economy — if needs be. Of the many methods of 

 purification, by chemical precipitation, by electrical decomposition, 

 I shall not weary you with, but proceed to the next stage of my 

 subject, namely, that of fermentation, and afterwards, more 

 particularly, to that of ammonical fermentation. 



Fermentation is the name given to the phenomenon of change 

 which takes place when saccharine and other liquids, are acted 

 upon by micro-organisms at their proper life-temperatures, the 

 word fermentation being derived from fervere to boil. When the 

 minute organism known as Saccharomyces cerevisce grows and 

 multiplies at a temperature of 25° to 35° C. in sugar solutions, 

 alcohol, carbon dioxide and some other bodies are formed ; 100 

 parts of cane sugar or 105-26 parts of grape sugar yielding on 

 fermentation: — Alcohol 51*11 per cent.; carbon dioxide 48*89 

 per cent.; succinic acid 067 per cent.; glycerin 3*16 per cent. 

 Thus, out of one hundred parts of cane sugar, about ninety-five 

 parts are decomposed, four parts disappear and form succinic acid, 

 glycerin and carbon dioxide, while one part is added to the newly- 

 formed ferment. 



The chief body sought for in fermentation is alcohol, and here 

 we have our fourth arabic word, al-Kohol. The word alcohol 

 means in arabic 'the finest powder,' and at one time denoted the 

 fine powder used by ladies to beautify the eyes ; a fine metallic 

 powder being used in the East to stain the eyelids. With the 

 early alchemists, it meant a sublimate or anything in a very fine 

 state of division ; flowers of sulphur, for instance. It was prob- 

 ably applied to finely powdered quicklime, which if used to 



