POPULAR MISCELLANY. 



709 



ing off a little of the liquid, when, if it is of 

 a pale straw-color, the quantity of indigo 

 will not be so great, but the quality will be 

 better than when it is of a deep-yellow 

 tinge. The liquid, when it is drawn off af- 

 ter fermentation, is always of a more or less 

 deep-yellow color. It is allowed to remain 

 for some little time, and is then, while still 

 warm, beaten with long bamboos for two or 

 three hours. It gradually becomes of a pale- 

 green color, and the indigo forms into small 

 flakes. The mass is allowed to remain for 

 half an hour, and the water is then turned 

 off gradually by withdrawing one by one 

 corks which have been placed at different 

 levels in the vat. The water is returned to 

 the river, and the deposit, which resembles 

 a thin scum, is carried through a trough 

 into a deep trench. It is then brought up 

 and boiled for a short time to prevent a 

 second fermentation, which would turn it 

 black and spoil it. After about twenty 

 hours, it is again boiled for three or four 

 hours ; then poured off, and strained through 

 a filter. A thick, deep-blue paste, almost 

 black, remains on the cloth of the filter af- 

 ter the liquid has been strained through. 

 This paste is exposed to a pressure, which 

 removes every particle of moisture, after 

 which the indigo is found in a large, thick 

 block, the cutting of which demands ex- 

 treme care. The blocks are put in the dry- 

 ing-ground, a large brick building from 

 which the light of the sun is carefully ex- 

 cluded, and, after from three to four days, 

 are ready to be sent to the market. 



Parificatioa of River- Water by Organic 

 Agents. Mr. R. Warrington, in " The Chem- 

 ical News," notices that, in the discussions 

 on the qualities of river-water, the destruc- 

 tion of sewage which takes place in such 

 water is in every case referred to the oxi- 

 dizing influence of the air, and the action 

 of organic agents is overlooked. Yet it is 

 evident, and generally admitted, that these 

 agents play an important part in the change 

 of organic into inorganic matter. The pro- 

 cess is in effect the joint work of a num- 

 ber of independent organisms having differ- 

 ent functions, the action of one class fol- 

 lowing that of another, and each carrying 

 the process through a particular stage. 

 First are the fungi, whose main function 



is apparently the rapid oxidation of carbon ; 

 then come the bacteria, embracing many 

 families of similar physical structure, but 

 endowed with very different chemical pow- 

 ers. One class attacks nitrogenous organic 

 matter and liberates nitrogen in the form 

 of ammonia ; another determines the con- 

 version of carbonaceous organic matter into 

 inorganic carbonic and nitric acids. Lastly 

 come the chlorophyl-bearing plants to con- 

 sume these products of the lower organisms ; 

 they also have the property of assimilating 

 urea and inorganic ash constituents. These 

 organisms must follow in their order, or 

 they will fail to do their work. Sewage 

 will finally be destroyed in a river of 

 adequate temperature, unless the natural 

 agents of oxidation are excluded by the 

 addition to the water of chemical refuse 

 fatal to organic life, or unless vegetation is 

 prevented by artificial means. Tempera- 

 ture and light, or rather darkness, are im- 

 portant factors in the process. The experi- 

 ments show that the oxidation in rivers in- 

 creases as the temperature rises. The 

 amount of dissolved matter in rivers is 

 found to be greatest in February, when or- 

 ganic action is suspended, and least in Sep- 

 tember and August, when the action is most 

 energetic. 



Mind in AVork. It is set forth on the 

 highest authority that whatever we do should 

 be done with our might. This precept being 

 interpreted means that there should be mind 

 in work. The difference between a work of 

 art and the product of machinery lies in the 

 presence of a mark of mind directing the 

 handiwork in the one case, while the other 

 is simply a predetermined result produced 

 by a duly formulated process wherein or 

 whereby physical forces are directed and 

 controlled by other physical forces on a sot 

 plan, to perform a defined series of actions, 

 which must, in the nature of things, end in 

 the production of the effect foreseen. Mind 

 sets the one process, or scries of processes, 

 in operation, and they work out their phys- 

 ical destinies. In the other, mind is the 

 active controlling power throughout. Start- 

 ing from these premises, we are now con- 

 cerned to point out that little or no success 

 can be expected in any calling which does 

 not suit the temper and bias of the mind 



