fect performance, and yet Mr. Proctor finds it profitable to present expensive bills at trifling admission fees, while paying the salaries of more than twelve hundred employees each week.

PRELIMINARY PROGRAM AMERICAN CLIMATOLOGICAL ASSOCIATION.

The twenty-first annual meeting of the Association will be held in the Banquet Room of the Aldine Hotel, Chestnut street, above Nineteenth, Philadelphia, on June 2, 3 and 4, 1904.

The Council recommends that papers should not exceed fifteen minutes in reading, and that members in discussion be limited to five minutes, unless special permission be granted; also, that members have duplicate copies of their papers, so that one copy may be deposited with the secretary immediately after being read. The headquarters of the Association will be at the Aldine Hotel, where the morning and afternoon sessions of the first day, Thursday, June 2, will be held. At the close of the afternoon session there will be a trolley excursion to Willow Grove, where a collation will be served, and later there will be an opportunity of enjoying the music.

The sessions of Friday, June 3, will be held at Houston Hall, of the University of Pennsylvania, when a midday luncheon will be tendered by the Provost and Trustees of the University.

The annual dinner of the Association will be held at 7.30 p. m., at the Aldine Hotel. The contribution to the dinner has been placed at five dollars.

NEW YORK AT WORLD'S FAIR.

The Empire State's pavilion at the World's Fair is peculiarly appropriate in commemorating the event on which the holding of the Exposition is based. The building is patterned after the University of Virginia, which was designed by Thomas Jefferson, during whose administration as President of the United States the territory comprising the Louisiana Purchase was acquired from France.

The building is on the State plaza with the Illinois and Iowa buildings for neighbors. The land falls off about 25 feet on the easterly end, and it has been taken advantage of by the architect to place a large fountain in the façade of the podium or terrace on which the building stands. This fountain typifies the Mississippi River in the form of a river god controlling the sea.

The building proper stands on a podium enriched with balustrades and vases. It is colonial in design and detail, and is surmounted with a low dome. One enters a large hall, 60 feet square, running the full height, arched and domed in the Roman manner, with galleries around the second story. To the right is a large assembly hall, 50x60 feet, to be used on State occasions, but it is really made a part of the grand hall. Small assembly rooms are included in the end of this wing. To the left of the hall are waiting and writing rooms, with retiring rooms and toilets for visitors. The whole first floor is as one room, however, and with its colonnades and arches will present interesting vistas.

The second floor contains suitable rooms for the commission, the secretary and general officers. The halls and all of the appointments are most generous, and are to be treated in a simple, quiet manner. No effort will be made in the way of elaborate decorations, but the beauty of the whole will depend entirely on carefully studied detail and correct architectural lines. In the large hall, it is proposed to place four large paintings in the lunettes, symbolizing the four original ownerships-the Indians in one, Spanish, French and Americans in the others. The four pendentives will be filled with pictures emblematic of the four original States included in the purchase; and their products and manufactures. The external sculpture, while not expensive, will receive careful attention. The fountain, already described, and the four quadriga flanking the dome, will be modeled by representative sculptors, and will typify the march of progress. The building will be of staff.

One fact in connection with the original purchase will receive recognition in the way of tablets and inscriptions, and that is that Robert R. Livingston, of New York, who was Minister to France under Jefferson, negotiated the treaty with Napoleon for the Louisiana Purchase. He was empowered to negotiate for the mouth of the Mississippi River, and from this the purchase of the whole tract followed. Monroe, afterward President, resigned as Governor of Virginia to carry special instructions from Jefferson to Livingston in regard to the detail of the transfer.

Other details of interest will be the embodiment of the capitals designed by Jefferson with Indian corn as a motive. The grounds are to be made particularly interesting by New York nurserymen, who will exhibit the many varieties of flowers and shrubs grown in the State, and no detail is to be left unstudied to make the whole an artistic success.

THE SANITARIAN.

JUNE, 1904.

NUMBER 415.

METHODS AND INTERPRETATION OF WATER ANALYSIS.

BY A. ROBIN, M. D.,

Bacteriologist to City Water Department, Wilmington, Del.

The average consumer judges of the quality of the drinking water by means of his special senses of sight, smell and taste. Water which is turbid or emits a disagreeable odor is unreservedly condemned, while clear, sparkling water free from odor is just as unqualifiedly pronounced "pure." Those of us who are familiar with the history of typhoid epidemics and have had opportunity to examine drinking waters by means of special methods know how fallacious such a crude judgment is. Water that is clear and sparkling may contain the germs of typhoid fever or may be polluted with sewage which, in the course of decomposition, gave rise to carbonic acid. It takes many billions of bacteria to render a glass of water perceptibly turbid, and it requires considerable fresh sewage to impart to it a fecal odor. On the other hand, a turbid water, although objectionable from an esthetic point of view, may be entirely wholesome, and a disagreeable odor may be due to inoffensive vegetable compounds or harmless algæ.

This evident inability to form a ready judgment of the quality of a drinking water has led the sanitarian to seek the aid of the chemist, who, it was supposed, could readily detect by means of chemical analysis the injurious substances in the water under suspicion. However, it soon became evident that a chemical

analysis of water for sanitary purposes differs essentially from any other kind of analysis which the chemist may be called upon to make. The finding of arsenic or some poisonous alkaloid in a suspected fluid is decisive, and a report on such finding is merely a statement of fact. In the analysis of water, on the other hand, the findings are purely relative and must be properly interpreted before they can be of any value. A drinking water, if I may borrow the legal phraseology, is indicted on circumstantial evidence, and it depends on the erudition and ability of the chemist to so interpret and connect the evidence as to make out a clear case for or against the suspected water,

The object of a chemical analysis of water is to discover whether or not pollution with objectionable organic impurities has taken place. By "objectionable organic impurities" we understand those which are from human or animal sources and are capable of conveying the germs of disease. In other words, we look principally for fecal contamination, inasmuch as the germs of typhoid fever, cholera, dysentery and other intestinal disorders are excreted with the feces and together with the feces gain access to the water. By itself, organic matter in the minute quantities in which it is present in water, is not injurious to health, even if derived from sewage. It is only because this organic matter may be the carrier of disease germs that it becomes a matter of serious consideration. Therefore, organic matter derived from plants or vegetables removed from the possibility of infection with disease-producing bacteria has no significance from a sanitary standpoint, and its presence in drinking water in no way renders it unwholesome.

It is thus evident that the aim of the sanitary chemist is to discover, first, the presence of organic matter, which would indicate pollution, and, second, to determine the source of this organic matter. How well these two requirements are fulfilled by a chemical analysis will be made clear later.

Dead organic matter in water, as elsewhere, is not in a state of stability. Through the agency of certain bacteria, in the presence of oxygen, it continuously undergoes material changes, becoming resolved into simpler inorganic compounds. The nitrogenous

substances are converted into ammonia, and the latter into nitrous and finally nitric acid, the two acids combining with bases usually present to form nitrites and nitrates, respectively. These changes may be best illustrated by the following scheme:

This process, may it be remarked in passing, is a beneficial one, since by its means purification of polluted water is accomplished and the decaying organic matter converted into useful plant food. These changes, under favorable conditions, take place incessantly so long as there is a supply of dead organic matter and the necessary bacteria are present. Therefore, the amount of organic matter in water represents that portion which has not yet undergone disintegration-the organic nitrogen or so-called albuminoid ammonia-as well as the various intermediary products of the portion which has undergone or is undergoing disintegrationfree ammonia, nitrites and nitrates. The quantitative relation of these products of oxidation to each other as well as to the unoxidized nitrogenous matter will depend on the original amount of the organic matter and the rapidity with which oxidation has taken place. Therefore, an analysis which discloses these various stages of oxidation reveals also not only the presence but the retrogressive course of the organic matter. Given a water containing relatively large amounts of albuminoid and free ammonia, together with nitrites and nitrates, the indications would be that such water contains a large amount of organic matter in a state of incomplete oxidation; in other words, the contamination is recent. On the other hand, the presence of nitrates, in the absence of nitrites, with only small amounts of free and albuminoid ammonia, would indicate complete oxidation or a previous pollution. goes without saying that pure water should contain only traces of albuminoid and free ammonia and should be free from nitrites and nitrates, the latter, if in small quantity, being rapidly appropriated by the water plants. It is to be expected that in deep wells removed from the possibility of pollution, the water will contain very slight amounts of ammonia and no nitrites or nitrates, or mere traces, although free ammonia may sometimes be present in large amounts as a result of oxidation of vegetable matter or nitrates by ferric oxide.

It

In addition to organic matter, water contains various salts, the most important and constant of which is sodium chloride, or, occasionally, magnesium and calcium chloride. These chlorides are derived from the sea or geological formations rich in salts. The