emorial to her husband. The
results attained are described below, and show that an opportunity is
open for a very important and extensive investigation in this branch of
astronomical physics. Mrs. Draper has accordingly decided greatly to
extend the original plan of work, and to have it conducted on a scale
suited to its importance. The attempt will be made to include all
portions of the subject, so that the final results shall form a complete
discussion of the constitution and conditions of the stars, as revealed
by their spectra, so far as present scientific methods permit. It is
hoped that a greater advance will thus be made than if the subject was
divided among several institutions, or than if a broader range of
astronomical study was attempted.

It is expected that a station to be established in the southern
hemisphere will permit the work to be extended so that a similar method
of study may be applied to stars in all parts of the sky. The
investigations already undertaken, and described below more in detail,
include a catalogue of the spectra of all stars north of--24 deg. of the
sixth magnitude and brighter, a more extensive catalogue of spectra of
stars brighter than the eighth magnitude, and a detailed study of the
spectra of the bright stars.

This last will include a classification of the spectra, a determination
of the wave lengths of the lines, a comparison with terrestrial spectra,
and an application of the results to the measurement of the approach and
recession of the stars. A special photographic investigation will also
be undertaken of the spectra of the banded stars, and of the ends of the
spectra of the bright stars.

The instruments employed are an eight inch Voigtlander photographic
lens, reground by Alvan Clark & Sons, and Dr. Draper's 11 inch
photographic lens, for which Mrs. Draper has provided a new mounting and
observatory. The 15 inch refractor belonging to the Harvard College
Observatory has also been employed in various experiments with a slit
spectroscope, and is again being used as described below. Mrs. Draper
has decided to send to Cambridge a 28 inch reflector and its mountings,
and a 15 inch mirror, which is one of the most perfect reflectors
constructed by Dr. Draper, and with which his photograph of the moon was
taken. The first two instruments mentioned above have been kept at work
during the first part of every clear night for several months. It is now
intended that at least thr