M. MATEEIA MEDICA, THERAPEUTICS, AND HYGIENE. 535 



M. MATERIA MEDICA, THERAPEUTICS, AND 



HYGIENE. 



WATER KEPT SWEET BY THE IMMERSION OF IRON. 



It is stated that if a piece of polished iron be immersed in 

 water its surface becomes rusty, owing to the absorption of 

 oxygen from the water. If, however, a second piece of iron 

 be introduced after a time, this will not rust, and the water 

 will be found to retain its sweetness and purity for a long 

 time unchanged. 10 (7, January 14, 12. 



FUNGI IN POTABLE WATER. 



Professor Frankland has lately been renewing the experi- 

 ments of Dr. Heisch in regard to the development of fungi in 

 drinking-water, in the course of which he found that when 

 sugar is added to waters contaminated with sewage a fer- 

 mentation ensues, with a rich growth of fungi. Meeting some 

 unexpected exceptions, however, in the course of his investi- 

 gations, to the result indicated above, he instituted a series 

 of experiments, and finally deduced the following general re- 

 sults, according to the Chemical JVeios : 



1. Potable waters mixed with sewage, urine, albumen, and 

 certain other matters, or brought into contact with animal 

 charcoal, subsequently develop fungoid growths when small 

 quantities of sugar are dissolved in them, and they are ex- 

 posed to a summer atmosphere. 



2. The germs of these organisms are present in the atmos- 

 phere, and every water contains them after momentary con- 

 tact with the air. 



3. The development of these germs can not take place 

 without the presence of phosphoric acid, or a phosphate, or 

 phosphorus in some form of combination. Water, however 

 much contaminated, if free from phosphorus, does not pro- 

 duce them. 1 A, February 10, 68. 



SEWAGE WATER. 



Dr. Letheby continues his crusade against the use of sew- 

 age water for manure, maintaining, as he does, that it is a 

 most prolific source of entozoa in man and the lower ani- 



