Even to those who are familiar with the application of meteorological science to the making of weather forecasts, and with the material benefits accruing to the commerce and industry of the United States from timely warnings of marine storms, frosts, and cold waves, it will be interesting to note that at the time of the founding of the first of the thirteen original Colonies, at Jamestown, Virginia, in 1607, practically nothing was known of the properties of the air or of methods for measuring its forces. To-day electrically recording automatic meteorological instruments measure and transcribe for each moment of time at two hundred stations in the United States, the temperature, the air pressure, the velocity of the wind, the direction of the wind, the beginning and ending of rainfall, with the amount of precipitation; and the presence of sunshine or cloud; and three thousand voluntary observers each day record the temperature and the rainfall. That we live in an age of great intellectual acumen, and that he is indeed a wise prophet who can even dimly outline the possibilities of the next century, is fitly shown by the development of meteorological science during the recollection of the present generation; although one must admit that in the making of weather forecasts, valuable as they are, we have not advanced beyond the partly empirical stage. It is, therefore, improbable that in the making of these forecasts we shall ever attain the accuracy acquired by theoretical astronomy in predicting the date of an eclipse or the culmination of any celestial event. It was not until 1644, twenty-four years after the landing of the Pilgrims at Plymouth Rock, that Torricelli discovered the principle of the barometer and rendered it possible to measure the weight of the superincumbent air at any spot where the wonderful yet simple little instrument might be placed. Torricelli’s great teacher—Galileo—died without knowing why nature, under certain conditions, abhors a vacuum, but he _had_ already discovered the principle of the thermometer. The data from the readings of these two instruments form the base of all meteorological science. Their inventors as little appreciated the value of their discoveries as they dreamed of the coming great western empire which should first use their instruments to measure the inception and development of storms, and later, with the aid of the electro-magnetic telegraph, to give warnings to threatened regions of the approach of hurricanes, cold waves, floods, and frosts that have been worth at least one hundred million dollars to this country during the past ten years without counting the many thousands of lives saved among mariners.