LETTER OF TRANSMITTAL

Hon. JAMES WILSON,

U. S. DEPARTMENT OF AGRICULTURE,

WEATHER BUREAU,

Washington, D. C., May 25, 1898.

Secretary of Agriculture, Washington, D. C.

DEAR SIR: I have the honor to transmit herewith a brief report on the temperature and rainfall, and some other climatic features of the Island of Cuba, which has been somewhat hastily compiled by Dr. W. F. R. Phillips of this office and, also, a note on the weather of Manila.

Meteorological information regarding the Island of Cuba is very scant, and the data compiled in the various tables of the accompanying report represent about all the precise meteorological information. to be had for the Island. For the purpose of comparison, the temperature, rainfall, and number of rainy days at Washington, D. C., and New Orleans, La., have been introduced in several of the tables (Nos. 1, 2, and 3), the data being printed in bold-faced type to attract special attention. It will perhaps not be inappropriate to emphasize several points upon which there may be misapprehension. The average summer temperature (June, July, and August) of Habana is 82.0° F., that of New Orleans, 81.6° F., and that of Washington, 75.0° F. The highest temperature recorded in ten years at Habana was 100.6° F., while at Washington the highest temperature has been 104° F. The average annual rainfall at Habana is 51.73 inches, and is less than that at New Orleans, which is 60.52 inches; the rainfall at Washington is 44.70 inches. On page 11 will be found an interesting analysis of the rainfall for thirty years at Habana. During this period five occasions have happened when as much, or more, rain fell in the usual "dry season" as in the "rainy season." The average amount of rain falling in the "rainy season," which extends from May to October, is 32.37 inches. In the same months, the average rainfall for New Orleans is 27.00 inches, and for Washington, 24.10 inches.

I recommend that the report be printed as a bulletin of the Weather Bureau.

CLIMATE OF CUBA.

INTRODUCTION.

There appears to be very little precise and accurate information obtainable regarding the climate of Cuba. Ramon de la Sagra, in his Historie Physique de Cuba, quotes, as the earliest record he had consulted, a year's observations of the barometer and thermometer made in Habana in 1794. The thermometer readings, however, appeared to be in error from some cause or other not known and were considered too inaccurate to use. Trustworthy observations of temperature were made in Habana by D. Antonio Robledo, in 1800, 1801, 1806, and 1807, and by D. Joseph Ferrer, in 1810, 1811, and 1812.

Systematic meteorological observations were begun in Habana about 1850 and kept up for some years by Andre Poey, but the data were probably not published, at least no reference to them can be found in the very complete index of meteorological data of the Weather Bureau.

At only one station have systematic meteorological observations been made and published for any considerable time, and that is the observatory of Belen College, Habana. Observations were begun at Belen College in 1859 and have been continued to the present. The daily meteorological observations made at Belen College have been published with more or less regularity in annual volumes. With one or two exceptions, and then only for relatively short periods, no compilation of the monthly averages has been published.

Apart from the observations of Belen College and the brief records already named, only fragmentary meteorological data for other parts of the island have been found. Temperature observations made in 1796-99 at Ubajay, a village about 15 miles southwest of Habana; two years' observations between 1832 and 1835 at Matanzas; eighteen months' observations in 1839 and 1840 at a place in the interior about 150 miles eastward of Habana, the San Fernando mines; and fragmentary observations at Santiago de Cuba and Trinidad de Cuba comprise all the data to be found.

A good deal of meteorological data, especially of rainfall, is, however, to be had for adjacent and neighboring islands, and which by judicious use may be made to be of considerable service in forming an intelligent idea of the climate, or climates, of Cuba. With this purpose in view, temperature and rainfall data have been compiled from the following places, viz: To the north, Key West, Fla., and Nassau, Bahamas; to the east, Port au Prince, Haiti, San Juan,

Puerto Rico, and St. Thomas; and to the south, Kingston and other stations in Jamaica. To the west there are no islands, and the nearest meteorological station is at Merida, Yucatan. Also for general information and because of some climatic relevancy that may exist, meteorological statistics from the islands of Martinique, St. Vincent, Barbados, and Trinidad have been compiled and introduced. The different statistics are shown more or less in detail in the tables to be found in the text, or appended thereto.

GEOGRAPHICAL POSITION.

With the exception of the northern part of the Bahamas, the large group of islands collectively known as the West Indies lies. within the north tropical zone, being situated in the greater part between the Tropic of Cancer and the tenth parallel of north latitude, and between the sixtieth and eighty-fifth meridians of west longitude. The total number of islands comprising the West Indies is somewhat more than 1,000, and the total land area is, in round numbers, about 95,000 square miles. Cuba, Haiti, Jamaica, and Puerto Rico, which comprise little more than three-fourths of the total area of the West Indies, are virtually included between the parallels of 17° and 23° north latitude. The greater part of the land area lies at a considerable elevation above sea level; more than 15,500 square miles lie at an altitude of 1,500, or more, feet above the sea. The Bahamas are the lowest and rise but little above the sea, the highest hill being only 230 feet.

The area of Cuba and its dependent islands is about 43,000 square miles. Its extreme length, measured along a curved line following its center, is 730 miles, and its average breadth about 80 miles. The physical aspect of the interior of Cuba, according to Humboldt, "is gently undulating and like that of England, not more than 280 to 380 feet above the level of the sea. The village of Ubajay, about 15 miles distant from Habana, in a southwesterly direction, is 242 feet above the sea."

The highest part of the island is the range of mountains known. as the Sierra Maestra, bordering the southeast coast from Cape Cruz to Cape Maysi. The highest mountain peaks are the Pico de Tarquino, 7,670 feet, the highest point in the island; Gran Pedra, 5,200 feet; Junque and Ojo del Toro, 3,000 feet. From this range there extends very nearly through the center of the island a general ridge of very much less elevation, though in the extreme western part it rises, in the Pan de Guajaibon, to an elevation of 2,530 feet. This ridge divides the island into two general watersheds, from which its rivers flow in northerly and southerly directions, respectively.

CLIMATE.

The climate of the West Indies presents, with respect to both

temperature and rainfall, considerable variations from the generally conceived idea of tropical uniformity. These variations are largely, if not entirely, caused by differences in altitude and position with respect to the prevailing winds of the zone.

Meteorologically considered the West Indies lie between the sealevel isotherms of about 77° and 80°, and have an average annual rainfall of about 60 inches, the greater part of which falls from May to October. The average humidity of the atmosphere is approximately about 75 per cent of the amount required for saturation at the average annual temperature. The prevailing winds are from the east and north of east, the "northeast trades," and blow with great regularity and uniformity.

TEMPERATURE.

The average annual temperature of Habana, as determined from the observations at Belen College, made during the decennium 1888-1897, may be stated in round numbers as 77° F. In this decennium the highest annual temperature was 77.2°, and this occurred upon three occasions; and the lowest annual temperature was 76.1°, and happened upon only one occasion, showing in the ten years an extreme range in annual averages of but 1.1° F. It would, therefore, seem probable that the mean temperature for the decennial period 1888-1897 is about a true average for Habana for any long period. The warmest month at Habana is July, with an average temperature of 82.4° F. The warmest July in this decennium had an average temperature of 83.5° F., and the coolest July a temperature of 81.7° F. The warmest single month in the decennial period was August, 1888, when the average temperature was 84.2° F. The coldest month is January with an average temperature of 70.3° F., and the warmest and coldest Januaries in this decennium were, respectively, 73.4° F. and 67.5° F. The highest temperature recorded was 100.6° F. in July, 1891, and the lowest, 49.6° F. in February, 1896.

For Matanzas, on the coast about 50 miles east of Habana, there is a record for two years, beginning in August, 1832, and ending in July, 1833, and again beginning in January, 1835, and ending with December of the same year. From this record the mean annual temperature at Matanzas appears to be about 78°. The highest temperature is recorded as 93°, and the lowest as 51°.

At Santiago, on the extreme southeast coast, the temperature is apparently higher than on the northern and western coasts, and from the meager data available appears to be about 80°, with an average difference between the warmest and coldest months of about 6° F. A very short fragment of a record of temperature has been found for Trinidad de Cuba, about midway on the southern coast, giving the average temperature from December, 1851, to March,