per hour, the pressure of the wind in pounds past year those in the larger cities have con- Plaister Cove, Nova Scotia. The following is a list of the stations occupied by observer sergeants on the 1st of October, 1872. It is to be observed that the stations in the Dominion of Canada though working isochronously and in harmony with those of our Signal Service Bureau, are under the control of the Dominion Meteorological Bureau, and are supported by the FLEE Lake City, Florida. New Orleans, La. San Francisco, Cal. St. Louis, Mo. Omaha, Nebraska. Virginia City, Montana Ter. Alpena, Mich. Two observer sergeants were also sent per or Western Lakes, are Lakes Superior, out, one with the North Polar Expedition under command of Captain C. F. Hall, the other to the Island of St. Paul, Alaska, where a station is to be established. More than one hundred other applications were made for the establishment of stations in every part of the country, which were necessarily declined for the time from the want of both means and men. The different parts of the country are designated as follows in the "Synopsis and Probabilites" of the Signal Service office : The six New England States are alluded to as New England, the Northeast, or the Eastern States. New York, New Jersey, Pennsylvania, Maryland, District of Columbia, and Virginia, as the Middle States, or sometimes as the Middle Atlantic States. North Carolina, South Carolina, Georgia, and Northern and Eastern Florida, as the South Atlantic States. Western Florida, Alabama, Mississippi, Louisiana, and Texas, as the Gulf States. Sometimes the Gulf States, the South Atlantic, West Virginia, Tennessee, Kentucky, and Arkansas, are grouped together as the Southern States. The Lower or Eastern Lakes, when used, mean Lakes Erie and Ontario. The Up Huron, and Michigan. The Northwest, popularly means the country lying between the Mississippi and Missouri Rivers. The Southwest means Texas, the Indian Territory, and New Mexico. The Pacific Coast or Pacific States, includes California, Oregon, and Washington Territory. The Ohio Valley includes the belt of country about two hundred miles broad, between Pittsburg and Cairo. The Mississippi Valley includes a belt of somewhat greater width from below Vicksburg to Davenport, Iowa. The "Extensions" from one State to another, refers to areas reaching to the central portion of the State mentioned. In Coast is included the land between the water edge and the Coast hills or mountains which skirt them. Winds are said to blow from the Northeast when they are included within the quadrant from north to east, and similarly for other directions. There are certain principles or laws deduced from observation in regard to the direction which the wind will take in an approaching storm, the relative amount of humidity found in advance of a storm and in its rear, the path which the central area of low pressure will pursue, and the velocity which the storm will acquire in | required in their duties, and with seven blank its progress, which very much aid the meteorologists in predicting the character of a given storm, but the main points can be learned by looking at the map on the opposite page. We have said that the observer sergeants, and we might add, their assistants also, were trained men. Their training is very thorough, and requires a considerable time and practice to make them perfect. The cost of fitting up each station is considérable, requiring a room near and readily accessible to the telegraph office from which the reports are to be sent, and if practicable also a table or desk at that office for the preparation of the reports and the translation and transcription of those received from the principal office, a roof strong enough for the erection of the apparatus for determining the velocity, direction, and force of the wind, and if practicable the transmission of these particulars to a self-registering apparatus in his room. The instruments supplied to each station are, one standard barometer (Green's, Signal Service, U. S. A.); one standard thermometer (Green's, Signal Service, U. S. A.); one standard hygrometer (Glaisher's Model); one maximum thermometer (Signal Service U. S. A.); one minimum thermometer (Signal Service, U. S. A.); one anemometer (Robinson's); one large wind vane (Signal Service, U. S. A.), and one smaller wind vane (Signal Service, U. S. A.); one rain gauge; one clock of excellent quality and carefully adjusted to the local time. The observers are required to correct each of the barometrical observations for instrumental error, for temperature, and for elevation, before sending them to Washington. They are required to follow their instructions, which are very carefully prepared, in regard to the place and circumstances, and the reading of the thermometers and the hygrometer, and to see that the self-registering apparatus of the anemometer is in perfect order. They are also instructed in regard to the observations of the wind vane, and the rain gauge. They are further supplied with the necessary tools for cleaning and repairing their instruments and at the river stations with water gauges, or instructions how to make them, and at points where cautionary signals are to be displayed, with these, which we shall describe further on. They have also a full supply of the different forms, thirteen in number, books in which they are required to make their entries daily or weekly. They are furnished with ten or twelve books of reference, needed for the better understanding of their duties. The reports to the Signal Service Bureau are made in a prescribed cypher, very carefully and ingeniously arranged to give the maximum of information in the minimum of words. The table of cyphers have their separate word for each variation of a tenth or hundredth of a degree in thermometer or barometer, in the velocity of the wind, the character of the clouds, the rainfall, etc., etc. This will be best illustrated by an example. The report from the Mount Washington, N. H. station at a given date, is as follows: Turning to the Key to the cyphers we find the translation to be, reading from left to right, horizontally: Station, Mount Washington, N. H., date 2d October. Time, Morning Report, Barometer 30.07; Thermometer 19°; Humidity 35; Weather, Cloudy; Direction of Wind, Northwest; Velocity of Wind, 47 miles per hour; Upper Clouds, Hidden; Lower Clouds, Foggy; Rainfall, .01. The date and time in the upper line, and the weather and direction of the wind in the lower, being each expressed by a single word. If the station is a river port the afternoon report consists of twelve words arranged in two lines of six words each, the last word in the first line being River, and the last word in the second line indicating the change in the depth of water which has taken place in the previous twenty-four hours. These reports of the depth of water have proved of great value to the navigation of the Western rivers, often shortening the upward passage twelve or twenty-four hours. The following is an example of a River report: Orleans Gay Folks Trial By River Burns Ranche Hidden Ten Append Hang TRANSLATION.-Station, New Orleans; Date, 12th; Time, Afternoon Report; Barometer, 30.19; Thermometer, 74°; Humid The seventy or eighty reports having come into the Signal Service Office at Washington by 8 A. M., 5 P. M., and 12 P. M., let us next see how the weather map is filled up, and the "synopsis and probabilities" deduced from it. ity, 100; Weather, Heavy Rain; Direction | low barometer. The connecting lines drawn of Wind, Southeast; Velocity of Wind, 8 between places where the height of the miles; Upper Clouds, Hidden; Lower barometer is the same are called iso-baroClouds, Sky Covered; Rainfall, 88; River, metrical lines, i. e., lines of equal barometer, 9 inches rise. or for convenience, isobars. These isobars having been drawn, the existence of a storm in any part of the United States is readily made manifest, and the prevailing direction of the wind, its velocity, the rainfall, and the relative humidity of the atmosphere, the character and course of the clouds, and the As the reports come in every particular is temperature being taken into the account, it accurately and neatly entered, first in the is not difficult to predict with reasonable blank map for the particular district to which certainty the weather for the coming twentythe station belongs, as Eastern States, Mid- four hours. If a cyclone is on its way northdle States, Lower Lake Region, etc., and ward along the coast, or in the region of the then in a blank map of the United States great lakes, cautionary signals are ordered like the one we have inserted. It will be at the ports most exposed to danger from noticed that certain simple characters are the storm and the prudent navigator will employed to express the character of the delay his voyage, or if he braves the temclouds, the presence of rain, snow, or fair pest, take ample precautions against its weather, and arrows to denote the direction fury. These cautionary signals, a red flag of the wind, while the height of the ther- with black square in the center by day, and mometer and barometer, and the velocity of a red light from a lantern hoisted on a lofty the wind are expressed in figures, in the or- pole by night, when displayed at the signal der here stated. When these particulars office, and other prominent places throughhave been entered, either for the whole coun-out any city, signify, according to the official try or a particular section, the meteorologists statement from the Signal Service Office, as proceed to connect by lines made by a soft follows: blunt red lead pencil, all places in which the barometer stands at 30.00 (its average height at the level of the sea, though on the Western plains the average is about 30.20). These will always be continuous lines, curved indeed, and sometimes forming a part of an ellipse; next they proceed to connect the other points in which the height of barometer is the same, whether above or below 30.00, and these too always form continuous lines, those above 30.00 being on one side of the line of 30.00 and those below it on the opposite side. Where there is a difference of ten-hundredths between two places not very distant, as for instance, where at one the barometer stands at 29.85 and at the other at 29.95, the line is run midway between the two places, and that line is noted as the line of the mean or 29.90, or simply 90 as on the map. Where there is excessive heat or excessive depression of the mercury in the barometer, there is almost uniformly a tendency in these lines to enclose in an elliptical form a considerable area, and this area thus enclosed, is one where a storm with high winds, a hurricane, or cyclone prevails. These are called areas of high or 1. That from the information had at the central office in Washington, a probability of stormy or dangerous weather has been deduced for the port or place at which the cautionary signal is displayed or in that vicinity. 2. That the danger appears to be so great as to demand precaution on the part of navigators and others interested, such as an examination of vessels or other structures liable to be endangered by a storm, the inspection of crews, rigging, etc., and general preparation for rough weather. 3. It calls for frequent examination of local barometers and other instruments by ship captains or others interested, and the study of local signs of the weather, as clouds, etc. By this means those who are expert may often be confirmed as to the need of the precaution to which the cautionary signal calls attention, or may determine that the danger is overestimated or past. These cautionary signals have within the past three years, saved from shipwreck and destruction many scores of vessels, and are regarded by all navigators both on the ocean and on our inland seas, as of very great im |