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pital admissions were lower than any similar period since sanitary operations have been conducted on the present



The true source of the Chagres has never been accurately determined. It has, however, two principal branches, one (the larger) known as the Pequeni, rising in the Cordillera San Blas, which at that point forms the Continental Divide, very close to the Atlantic Coast. The other branch has its origin about twenty miles (by the river), above Alhajuela, at which point the French Canal Company established a gauging station.

Between Alhajuela and the Caribbean, the principal tributaries are the Gatun, Chilibre, Obispo, Gatuncillo and Trinidad, named in the order their of joining the Chagres. In the dry season these may be regarded as negligible, but during rainy months they become tropical torrents, with a volume not to be ignored. None of the tributaries have been followed to their source, with the exception of the Obispo, although the Isthmian Canal Commission has established gauging stations on the Trinidad and Gatuncillo, about eight miles above Gatun.

Few rivers show a greater variation in the amount of discharge at different periods of the year than the Chagres. In the dry season, it is a clear, quietly flowing stream, while during the rainy season it becomes a great river, subject to sudden and violent freshets and floods.

The following table shows the maximum, the minimum and the mean discharges at each of the three principal gauging stations operated by the Isthmian Canal Commission:


A scene on the Chagres River-Panama.

Isthmian-American & P.RR.News Agency & Advertising Bureau. A.Bienkowski


An analysis lately made by the Department of Sanitation of the Isthmian. Canal Commission has proven the purity of

Paraiso Spring Water,

Has even found it to be "As Good As Distilled Water."

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The gauging station at Gatun was established in May 1907, and while discharges have been measured there since that time, the observations have not been carried on for a sufficient time to permit their use as authoritative. Enough data has been secured however, from measurements made this year, to enable us to compute the discharge at 135 per cent. of that at Bohio.

The following table taken from the revised edition of General Abbot's book "Problems of the Panama Canal" will show the maximum discharge reached in the eight

greatest floods of the Chagres of which there is authentic

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*Note: The height reached during this flood was recorded only for Bohio; that at Gamboa being calculated by means of the relation, which has been found to exist between those two stations by subsequent observations.

The Chagres above Gamboa is a clear mountain stream, and in the dry season the amount of matter carried in suspension is so small that no observations were deemed necessary. However, experiments were made by the Isthmian Canal Commission of 1899-1901 in order to determine the amount of matter carried in suspension during the rainy season, with the following results: At Alhajuela it was found that the matter in suspension was .15 of one per cent. of the total volume of the water, and at Bohio .18 of one per cent.

As the result of a chemical analysis of the water of the Chagres by Dr. Arthur I. Kendall, Acting Chief of the Isthmian Canal Commission Laboratory, collaborating with Ricardo M. Arango, Division Engineer in charge of the hydrographic work of the Commission, it was found that at Gamboa there is an average of 228 parts of solid matter carried in suspension to every million parts of water

In the course of the Chagres river from the Sierra San Blas, its bed presents. varied geologic formations. At its source granite is found and pieces have been washed down, but little is known of the exact character of the country. Above Alhajuela, there is stratified limestone, sometimes. white but usually gray, which passes under the sandstone of the lower river. Lower down, between Alha

juela and Cruces, a compact calcareous sandstone presents itself, containing fossils of the upper Oligocene or Miocene period, while the bed of the river at Gamboa is composed of compact limestone. At Bohio, there is a fine-grained volcanic breccia, and at Gatun a moderately close conglomerate under a brownish, impure calcareous clay, the former containing fossils of the Oligocene age. Between Gatun and Limon Bay, the Chagres passes through a stretch of swampy lowlands reaching almost to the sea, where the river cuts through a range of low hills.

Meteorological Work on the Isthmus.

This work could not be considered as fairly established by the Isthmian Canal Commission until January 1, 1906, when there were in operation two first class meteorological stations, Ancon and Naos, and twelve rainfall stations,Cristobal, Gatun, Bohio, Tabernilla, Bas Obispo, Gamboa, Alhajuela, Empire, Culebra, Rio Grande, La Boca and Panama. Of these, the stations at Ancon, Naos, Cristobal, Rio Grande and Bohio were using self-registering instruments. During the year Brazos Brook, Bas Obispo, Empire, Camacho, Culebra and La Boca were supplied with self-registering instruments and Bas Obispo was established as a first class meteorological station. This station is also equipped with an up-to-date evaporation plant, where experiments are being conducted to ascertain the daily, monthly and annual amount of evaporation. The Naos station was discontinued January 1, 1908, and consolidated with Ancon.

During the year 1907, Cristobal was established as a first class meteorological station, and the stations at Alhajuela, Gatun and Bohio equipped with triple registering instruments for recording the wind direction and velocity, sunshine, and rainfall.

There are now in operation on the Canal Zone three first class meteorological stations, at which the following observations are taken: Barometric pressure, temperature,

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