This is by the beautiful method of rock-crystal prisms, not the Rochon method of double-image, but by thin wedges cut to given angles.

I have told Mr.Alvan Clark my "experiences." and I hope he will apply his excellent mind to the scheme.

I am insisting upon this point in some astronomical twaddle which I am now printing, and of which I shall soon have to request your acceptance of a copy.
There is a very important department which calls for a zealous amateur or two, namely, 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.