Kitchener, indeed, goes so far as to recommend (with a _crede experto_) an _interval of sleep_ in the darkness of the observing-room before commencing operations.

I have never tried the experiment, but I should expect it to have a bad rather than a good effect on the eyesight, as one commonly sees the eyes of a person who has been sleeping in his day-clothes look heavy and bloodshot.
The object or the part of an object to be observed should be brought as nearly as possible to the centre of the field of view.

When there is no apparatus for keeping the telescope pointed upon an object, the best plan is so to direct the telescope by means of the finder, that the object shall be just out of the field of view, and be brought (by the earth's motion) across the centre of the field.

Thus the vibrations which always follow the adjustment of the tube will have subsided before the object appears.

The object should then be intently watched during the whole interval of its passage across the field of view.
It is important that the student should recognise the fact that the highest powers do not necessarily give the best views of celestial objects.