New England Meteorological Society.

OBSERVATIONS OF THUNDERSTORMS IN CO-OPERATION WITH THE UNITED STATES SIGNAL SERVICE: SECOND SEASON - 1886.

Thunderstorms will constitute a subject of special investigation during the summer months, on much the same plan as in 1885.

Volunteer observers to take part in the study are wanted in all parts of New England, except immediately about Boston, where enough are already enlisted.

The desired observations are classified as follows:

Class A. No instruments required. Simple records of the time of beginning and ending of rain, when thunder is first heard and loudest, and of the direction of wind and its changes.

Class B. Ordinary instruments needed. A thermometer and a tin can for collecting rain. A somewhat more detailed record of rain, wind, temperature, thunder, etc. during the passage of a storm.

Class C. Good instruments needed. Better measures of rain and temperature, with barometer readings if possible; and especially more careful observations on clouds.

The division into classes need not be closely followed. Observers of class A may add, for example, temperature of class B, or clouds of class C to their other subjects of record.

Days when observations are wanted:

(1). Observations are to be taken through June, July and August whenever a thunderstorm can be seen or heard.

(2). Observations are also desired at regular intervals from noon to six p.m. on certain days, whether a thunderstorm is in progress or not. These days will be called Term-days; they will be appointed one and a half to two days in advance by special message from the Chief Signal Officer in Washington, and will be announced to the public by telegraphic reports to all newspapers of the New England Associated Press. They will be days on which thunder-storms are expected. Most of the important newspapers have agreed to print these Term-day announcements.

Special circulars addressed to Yachtsmen and Pilots and to amateur photographers may be had on application.

Students who will observe, or who can suggest observers in New England towns, are requested to address W. M. Davis, Cambridge, Mass.