The investigations undertaken at the observatory may be divided into three classes: (1) The routine work of making observations of the local atmospheric conditions both by automatic registration and direct observation; and the reduction and publication of results. (2) The exploration of upper air by means of kites, and (3) Special studies of important topics by the observatory staff and visiting scientists.
The Blue Hill Observatory was established in 1885. Its report for 1886 shows the institution still in its formation period. The annual report for 1887, when it began to appear regularly in the 'Annals of the Harvard College Observatory,’ is almost complete, lacking only the hourly values of the relative humidity of the atmosphere, but more than making up for this by the very complete hourly record of cloud observations (from 7 a. m. to 11 p. m.). In the report for 1888 all
the usual meteorological elements are given; but thereafter hourly values of the precipitation and cloud observations alone are given, the other elements being recorded only in summary. The reason for this long backward step, for it certainly is such, was probably the desire to economize the time required for reducing the observations and the cost of printing, although it may have been thought that the publication of the hourly observations in extenso during two or three years was sufficient. This latter is not the case, however, for what we most lack in the study of the air conditions in this country is reliable hourly observations conveniently accessible through print. It is especially desirable to have these records when they are as carefully made as those at the Blue Hill Observatory. It must be remarked, however, that the proper reduction of automatic records is a very laborious task.
