The search will serve to illustrate a method often useful when a telescope has no finder.

Having taking out the eye-piece--a low-power one, suppose--direct the tube nearly towards Sirius.

On looking through it, a glare of light will be seen within the tube.

Now, if the tube be slightly moved about, the light will be seen to wax and wane, according as the tube is more or less accurately directed.

Following these indications, it will be found easy to direct the tube, so that the object-glass shall appear _full of light_.