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further : “ It was observed from the first that the animal and vegetable life which was so abundant and troublesome in the natural waters of the Nethe, lying over the spongy iron filters, had quite disappeared in the water, otherwise in exactly the same circumstances, lying over the sand filters, and I always supposed that this was due chiefly to mechanical filtration through the spongy iron having separated all the germs, spores, and seeds which came to life above it; but during the recent hot weather it has been found that the water from the “revolver,' though it contains all the impurities of the natural water, has been modified by the action of iron to such an extent that neither animal nor vegetable life is apparent over the sand filters. Without presuming to draw very wide inferences from this fact with reference to the action of iron upon organisms connected with disease, it may, at least, be pointed out that the absence of visible life in water treated with iron on a large scale confirms, in a great measure, the experiments of Dr. Frankland, Dr. Voelcker, Mr. Halton, Professor Bischof, and others."
For the sake of testing on a small and imperfect scale the efficiency of the iron and sand method of purifying water, I performed the following experiments : A water known to be polluted was obtained and analyzed ; then a quart of it was shaken for five minutes in a five-pint bottle with about one ounce of iron borings, filtered through sand and analyzed. Another portion of the original water was boiled about fifteen minutes, allowed to settle, and the quite clear liquid decanted and analyzed. This was for the purpose of comparing the effect of boiling with the other methods of purification. To another portion of the water some ferric chloride was added in such proportion that one part of metallic iron was used for 100,000 parts of water; it was allowed to stand five minutes and then filtered through sand. The following results were obtained :
POLLUTED WATER BEFORE TREATMENT.
. . . .
[The figures express parts per 100,000.]
. . . . . . Yellowish and in circles
Odor . .
None About twice as yellow as in first case . Ye!lowish and in small circles . . . . . . Foamy . . It blackens intensely
. . . 11.0000 • . . 4.6000 . . . 6.4000
3.0000 3.5000 0.8000 0.0308
0.0210 . . . . . 0.3000 . . . . . . None . . . . . 0.0360
. : 0.6435
. . . None Color . . . . . . . . . . . Nearly clear Evaporation .
. . Quiet Residue . .
. Uniform, yellowish Total solids .
. . 11.8000 Loss on ignition
. 3.8000 Fixed solids.
. . 8.0000 Hardness
· · · · 3.3000 Alkalinity . .
. . . . . 7.5000 Chlorine
. . . . . . . . . . 2.0000 Free ammonia .
0.0298 Albuminoid ammonia
0.0116 Nitric acid . .
0.3000 Nitrous acid . . . . . . . . . . . Trace Iron . .
0.1520 Oxygen for oxidation .
Another sample of polluted water was analyzed both before and after boiling, with the results given below. The figures express parts per 100,000. The first column represents the condition of the water before boiling, the second that of the water after boiling half an hour and settling. Odor . . . . . . . . Foul.
Slight Color . . . . . . . Yellowish.
Yellowish Evaporation . .
. Little foamy. Little foamy Residue . .
Yellow and in flakes. Yellow and in circles Ignition of residue . . . . . It blackens. It blackens some Total solids . . . . . 11.0000.
8.4000 Loss on ignition .
. . 4.6000.
2.8000 Fixed solids.
5.6000 Hardness . .
2.3000 Alkalinity . .
3.2000 Chlorine . . . . . . . 0.5000.
0.7000 Free ammonia .
0.0016 Albuminoid ammonia
0.0260 Nitric acid . . . . . . ..
Trace Nitrous acid . . . . . . . None.
None Iron . . . . . . . . 0.5000.
The experiments show that boiling for half an hour very materially changes the character of the water. The carbonates of the earth-metals are precipitated, thus softening the water ; much of the organic matter is also precipitated, and all germs are destroyed. Thus every family has at hand the best possible means for purifying its drinking-water. The water may be swarming with disease germs; it will come from the boiling kettle perfectly harmless and wholesome. There can be no objection to this method worth considering. It should receive the most hearty acceptance and practice by every family obliged to use water which is at all questionable. The labor and expense required for it are so trifling as to be insignificant. It is estimated that 30,000 people die in the United States, annually, from typhoid fever alone.
It appears to be well established that the majority of cases are communicated through water. Suppose 20,000 of the fatal cases were so contracted; then the precaution to boil drinking-water would save 20,000 lives annually, and a 100,000 hearts from mourning. But it would do more than this. Look at the list of diseases which the illustrations given in this paper show may be caused more or less directly by drinking impure or poisonous water: Colic, headache, erysipelas, sore throat, constipation, sore mouth, gastritis, pneumonia, dysentery, consumption, bilious fever, liver diseases, skin diseases, rheumatism, dyspepsia, and general debility. The boiling of drinking-water would save a host from pain and death. I desire to emphasize this because the remedy is so simple.
The experiments on the purification of water by iron give remarkable results, and fully confirm the claims made for the system at Antwerp. The germ theory of disease has assumed so much importance that whenever any system of water purification is proposed it is naturally asked whether it has any influence upon germs. I regret that time and opportunity have prevented us from making biological tests in connection with the experiments. I do not know that any one has experimented in this direction with the metallic iron and sand process, or with the ferric-chloride and sand method; but the following quotation very closely approaches the subject and is from high authority.
T. F. Frankland recently reported to the Royal Society of England a series of experiments upon the purification of water. In his paper, speaking of filtration, he said: “Thus green sand, coke, animal charcoal, and spongy iron were at first successful in removing all organisms from the water passing through them, but after one month's continuous action this power was in every case lost. The improvement still effected, however, by spongy iron and coke was very great indeed, while the green sand and brick-dust were much less efficient, and the number of organisms in the water that had been filtered through charcoal was greater than in the unfiltered water."
If the methods employed by Dr. Frankland did remove all organisms for a time, it is certainly encouraging. If any system is efficient for a time, its continued efficiency is, doubtless, possible. The importance of the subject leads us to make further inquiry about disease germs and water. They may be communicated, no doubt, by pure water, if they are in it. But do they prefer to live in pure water? Can they flourish in pure water ? Referring to wells more particularly, why is typhoid fever so closely associated with organically impure water, and not equally with pure water, if the natural process of filtration fails to remove disease germs? These questions do not seem to have been considered. Does the organic impurity in the water itself have nothing to do with their presence or their virulency? Why do biologists use nutrient preparations for the culture of bacteria? Why not, in the culture experiments, use distilled water alone? It is evident, germs require certain conditions to vitalize them; a grain of wheat which has fallen upon a stone will not germinate, but it responds to the touch of fertile soil. The principles of life are as fixed and as definite as any which govern in the mineral kingdom. If there is but one germ in the first place, millions will develop in a nutrient fluid in a short time; but if there is no nutrient fluid the germ will remain dormant indefinitely.
But how came the germ in the polluted well? It is easier to understand how it came to be in river water from the inflow of sewage containing the dejecta of patients. But is it not just as likely to be in this pure well as in that polluted one up among the hills ? On the ground of the germ theory of disease, how can sporadic and isolated cases of typhoid fever be explained,