CHAPTER VIII - SUGGESTIONS FOR OBSERVING ANNULAR ECLIPSES OF THE SUN

Summary

Previous to the celebrated eclipse of 1858, the Astronomer Eoyal circulated a useful series of suggestions, which we here reproduce, in a slightly amended form, as applicable to other eclipses besides the one above referred to: —

“ The following suggestions are offered as presenting grounds for consideration, which may tend to direct observers ia deciding on the employment of the means which they may possess.

“ I. Observations not requiring Instruments.

1. “ 1. As the eclipse advances, it is desirable to obtain some notion or measure of the degree of darkness.

2. “ 2. At what distance from the eye can a book or paper, exhibiting type of different sizes, be read?

3. “ 3. Hold up a lighted candle nearly between the Sun and your eye. At how many sun-breadths' distance from the Sun can the flame be seen?

4. “ 4. If you are in an elevated position, remark the changes of colour and appearance of the surrounding objects in the landscape.

5. “ 5. If you see the spots of light formed by the intersecting shadows of the boughs of trees, remark whether they exhibit the lunefonn of the Sun.

6. “ 6. When the annulus is formed, you will probably observe it with a darkened glass; but you are particularly requested to devote one instant (as early as possible) to the verification of this point, viz.: When the annular Sun is viewed with the naked eye, does it appear an annulus or a fully illuminated disc?