Analysis of the Croton and Schuylkill waters, by J. C. Booth, Professor of Chemistry to the Franklin Institute of Pennsylvania, and H. M. Boye, of Philadelphia.
| Croton Water. | Schuylkill Water. | |||
| In 100 parts | gr. in 1 gall. | In 100 parts | gr. in 1 gall. | |
| Carbonate of Lime, | 45.86 | 2.293 | 53.67 | 2.190 |
| Carbonate of Magnesia, | 18.78 | .939 | 11.87 | 0.484 |
| Alkaline Carbonates, | 16.57 | .828 | 4.53 | 0.185 |
| Alkaline Chlorides, | 3.87 | .193 | 3.75 | 0.153 |
| Oxide of Iron, | 2.21 | .110 | ||
| Silica, | 7.18 | .359 | 9.68 | 0.395 |
| Organic Matter, | 5.53 | .276 | 0.88 | 0.036 |
| Parts, 100.00 | grs. 4.998 | |||
| Alumina and Oxide of Iron, | 1.88 | 0.077 | ||
| Alkaline Sulphates, | 13.74 | 0.560 | ||
| Parts, 100 | grs. 4.080 | |||
The Croton water was taken from the Croton dam, and when perfectly clear was found, as appears by the above analysis to contain 4.998, or about five grains of solid matter to the gallon. The Schuylkill water was taken from the middle basin on Fair Mount, and contained 4.08 grains of solid matter to the gallon. The Croton differs from the Schuylkill water in containing a larger amount of the alkaline carbonates, and of the carbonate of magnesia, while it contains less carbonate of lime, and is entirely destitute of the alkaline sulphates, of which the Schuylkill contains 13.74 parts in 100 of the total solid matters, though amounting to only one half a grain to the gallon.
It appears from the above table, that the amount of impurities contained in the Thames water, exceeds those of the Croton by nearly six fold, and that the quantity of lime, held in solution in the former, surpasses that of the latter, about fifteen times. The Thames water differs also from the Croton, in the circumstance that it contains an appreciable quantity of chloride of sodium, or common salt of which the Croton is entirely free. There are but very few streams to be found, whose waters contain less than 4.16 grains of solid matter to the gallon. The carbonate of lime is held in solution by carbonic acid, forming bicarbonate of lime. By boiling, this acid is expelled, and the carbonate of lime is precipitated on the sides of the vessel, constituting the fur of the tea-kettle, and the crust of boilers. River water always contains a quarter or less quantity of organic matter in suspension or solution. As a general rule, the quantity is too small to produce any decidedly injurious effect, but physicians and medical writers agree in the opinion that water impregnated with it to any great extent must be deleterious. Where the quantity of decomposing matter is too small to produce any immediately obvious effects, it is difficult to procure any decisive evidence of its influence on the system. When the amount is considerable, it causes dysentery and fevers, often of a highly fatal character. In a trial at Nottingham, England, in 1836, it was proved that dysentery of an aggravated form, was caused in cattle by the use of water contaminated with putrescent vegetable matter, produced by the refuse of a starch manufactory. The fish, (perch, pike, roach, dace, &c.,) and frogs in the pond, through which the brook ran, were destroyed, and all the animals which drank of the water became seriously ill, and many of them died with the symptoms of dysentery. It was, moreover, shown, that the animals sometimes refused to drink the water, that the mortality was in proportion to the quantity of starch made at different times; and that subsequently, when the putrescent matter was not allowed to pass into the brook, but was conveyed to a river at some distance, the fish and frogs began to return, and the mortality ceased among the cattle. There are many instances on record where troops have sickened and many died of putrid fever and dysentery, from drinking the water of stagnant pools and ditches or of rivers, as of the river Lee, near Cork, (Ireland,) which, in passing through the city, receives the contents of the sewers from the houses, and is otherwise unwholesome.
The organic matter contained in river water consists chiefly of the exuviæ of animal and vegetable substances, but another class of impurities consists of living beings, (animals and vegetables.) The aquatic animals, which have, from time to time, been exhibited in this city by means of the solar microscope, are collected in stagnant pools, and are not found in river or well water. The quantity of organic matter contained in the Croton must be extremely small, as this, together with the silex, iron, and magnesia, amount to only 4/10ths of one grain to the gallon.
Well Water,—or pump water, as it is often called in cities, is essentially the same as spring water, but liable to impregnation, owing to the land springs filtering through the walls, and conveying impurities into it. This is sometimes prevented by lining them with cast-iron cylinders, or by bricks laid in water-cement. Dr. Percival affirms, that bricks harden the softest water, and give it an aluminous impregnation. The old wells must, therefore, furnish much purer water than the more recent, as the soluble particles are gradually washed away. It contains a greater proportion of earthy salts, and of air, and has a greater specific gravity than other spring waters. Owing to the fact, that it contains a larger quantity of bicarbonate and sulphate of lime, than river water, it decomposes and curdles soap, and is then denominated hard water, to distinguish it from those waters which mix with soap, and are therefore called soft waters. The reason that hard water does not form a pure opaline solution with soap, is, because the lime of the calcareous salts, chiefly the sulphate, forms an insoluble compound with the margaric and oleic acids of the soap. Here a double decomposition ensues, the sulphuric acid unites with the alkali of the soap, setting free the fatty acids, which unite with the lime to form an insoluble earthy soap. Hard water is a less perfect solvent of organic matter than soft water; hence in the preparation of infusions and decoctions, and for many economical purposes, as making tea and coffee, and brewing, it is much inferior to soft water, and for the same reasons it is improper as a drink in dyspeptic affections, causing irritation, and a sensation of weight in the stomach. The abundance of this earthy salt in the water of Paris, and London, of many parts of Switzerland and this country, cause uncomfortable feelings in strangers who visit these places. It is also said to produce calculous complaints in the inhabitants, a result which might be expected, owing to the low solvent power of the water not being sufficient to carry off the animal acid, which concretes in the kidneys to form calculi.[11] Well water can be easily freed from these earthy salts; boiling precipitates the carbonate of lime by driving off the carbonic acid which holds it in solution; and the addition of a little carbonate of soda precipitates the lime, if any exist in the water. Many persons prefer the taste of hard water to that of soft, and a change from one to the other, frequently causes a derangement of the digestive organs. The briskness, and rapidity of this and other water is owing to the air, and carbonic acid mixed with it. The air contained in water, has a larger proportion of oxygen than atmospheric air, and hence it is better adapted for the respiration of animals.
The water procured from wells in the city of New-York, has gradually been growing more and more impure, as the city has increased in size, until a very large proportion of it, is entirely unfit for culinary and dietetic purposes. That in the lower part of the city, has always been, more or less, brackish, owing to the percolation of the salt water from the north and east rivers through the loose sandy soil, thus giving them a distinct saline impregnation. The amount of impurities contained in these waters, varies, therefore, in different parts of the city, according to its elevation, and the denseness of the population. A gallon of water from the well belonging to the Manhattan Company in Reade-street, yielded 125 grains of solid matter; while the same quantity of water, from their well in Bleecker-street, yielded 20 grains, and in 13th street, 14 grains. A gallon of water taken from four of the city wells in the densely populated parts of the city yielded on an average, 58 grains each of solid matter.
The supply also of well water has been gradually diminishing in this city for the last several years. For example, at the Chemical Works on the North River, at 33d street, and at an extensive distillery on the East River, some distance above the Alms House, water cannot be procured in sufficient quantities on their premises, where, but a few years past, it was obtained in great abundance. At the Gas Works on the Collect grounds, where they have a well 20 feet in depth, by 18 feet in diameter, which, until 1834, furnished water freely, enabling the engine to raise 20,000 gallons in ten hours, in 1835 it required 14 to 16 hours to raise the same quantity, and in order to continue the supply, it was found necessary to return the water to the well, after using it for condensing the gas. The Corporation well, also, in 13th street, furnished, for several years, about 120,000 gallons of water daily, but in 1835, this quantity was reduced down to from five to ten thousand. In order to remedy this evil, a well was sunk at Jefferson Market, which in a short time deprived most of the wells in that vicinity, of water; thus drying up one source of supply, in order to increase that of another. There is, therefore, every probability that had not water been introduced into the city of New-York from abroad, the supply from the wells would, in a few years, have been insufficient for the economical, domestic and manufacturing purposes of the inhabitants. It is fearful to contemplate the amount of decomposing organic matter contained in the wells in the vicinity of Trinity, St. Paul’s, and St. John’s burying grounds, which for more than a century furnished the only water used by those residing in their neighborhood. No one can doubt that the use of such water, as well as that from the wells on the Collect, and over the greater portion of the city below Canal-street, must have proved extremely detrimental to the health of the citizens, and especially to children, and infants. We believe, therefore that the introduction of the Croton water, will increase the average duration of human life in the city of New-York, from 8 to 12 per cent. From 1815 to 1836, it ranged from 30.08 to 22.05, (in 1836), but the mean duration of life for the last 20 years is about 25 years; and the ratio of mortality, according to population, about as 1 to 35. From the manner, however, in which the inspector’s reports have been made, from the imperfection of the law, no great confidence can be placed in the returns,—those carried out of the city for burial, not having been included.
From a “Report on the subject of introducing pure and wholesome water into the city of Boston, by L. Baldwin, Esq., Civil Engineer,” it appears that the whole number of wells in that city in 1835, was 2,767. The water from 2,085 of these wells was drinkable, though brackish and hard, and 682 of them were bad and unfit for use. There were only seven of the city wells which yielded soft water occasionally and for washing, and from 33 of them the water was obtained by deep boring. “Within a few years,” says the Report, “it has become common in Boston, and the vicinity, to bore for water, and to make what are called Artesian wells. But no certain or valuable result has grown out of these endeavors. There are 33 bored wells, only two of which are stated as furnishing soft water. The same remarks will apply to the public wells of this city, the most of which produce nothing but hard and brackish water, and none of which is sufficiently soft to authorize its use in washing clothes,” &c.
Lake Water is a collection of rain, spring and river water, usually more or less contaminated with putrefying organic matter. It is generally soft, and when filtered, is as good and wholesome as any other description of waters. Though lake water cannot be characterized as having any invariable qualities; yet most of the Lakes of the United States, especially our great ones, afford a very pure water. In many of our smaller lakes the water is more or less stagnant, and of course very unhealthy.