the colors of double stars, for these have usually been noted after the eye has been fatigued with observing in illuminated fields.  The volume I hope to forward—­en hommage—­will contain all the pros and cons of this branch.

There is, for ultimate utility, nothing like forming a plan and then steadily following it.  Those who profess they will attend to everything often fall short of the mark.  The division of labor leads to beneficial conclusions as well in astronomy as in mechanics and arts.

    Mrs. Smyth and my daughter unite with me in wishing you all
    happiness and success; and believe me

    My dear Miss Mitchell,

    Yours very faithfully,

    W. H. SMYTH.

In regard to the colors of stars, Miss Mitchell had already begun their study, as these extracts from her diary show: 

“Feb. 19, 1853.  I am just learning to notice the different colors of the stars, and already begin to have a new enjoyment.  Betelgeuse is strikingly red, while Rigel is yellow.  There is something of the same pleasure in noticing the hues that there is in looking at a collection of precious stones, or at a flower-garden in autumn.  Blue stars I do not yet see, and but little lilac except through the telescope.

“Feb. 12, 1855....  I swept around for comets about an hour, and then I amused myself with noticing the varieties of color.  I wonder that I have so long been insensible to this charm in the skies, the tints of the different stars are so delicate in their variety. ...  What a pity that some of our manufacturers shouldn’t be able to steal the secret of dyestuffs from the stars, and astonish the feminine taste by new brilliancy in fashion. [Footnote:  See Chapter XI.]

    [NANTUCKET], April [1860].

MY DEAR:  Your father just gave me a great fright by “tapping at my window” (I believe Poe’s was a door, wasn’t it?) and holding up your note.  I was busy examining some star notices just received from Russia or Germany,—­I never knew where Dorpat is.—­and just thinking that my work was as good as theirs.  I always noticed that when school-teachers took a holiday in order to visit other institutions they came home and quietly said, “No school is better or as good as mine.”  And then I read your note, and perceive your reading is as good as Mrs. Kemble’s.  Now, being modest, I always felt afraid the reason I thought you such a good reader was because I didn’t know any better, but if all the world is equally ignorant, it makes it all right....

I’ve been intensely busy.  I have been looking for the little inferior planet to cross the sun, which it hasn’t done, and I got an article ready for the paper and then hadn’t the courage to publish—­not for fear of the readers, but for fear that I should change my own ideas by the time ’twas in print.

I am hoping, however, to have something