The grotesque forms of some of these are remarkable; and the variations the spots undergo from day to day are particularly interesting to the thoughtful observer.
A method of measuring the spots may now be described.

It is not likely indeed that the ordinary observer will care to enter upon any systematic series of measurements.

But even in his case, the means of forming a general comparison between the spots he sees at different times cannot fail to be valuable.

Also the knowledge--which a simple method of measurement supplies--of the actual dimensions of a spot in miles (roughly) is calculated to enhance our estimate of the importance of these features of the solar disc.

I give Mr.Howlett's method in his own words:-- "Cause your optician to rule for you on a circular piece of glass a number of fine graduations, the 200th part of an inch apart, each fifth and tenth line being of a different length in order to assist the eye in their enumeration.