Essays and addresses / by professors and lecturers of the Owens College, Manchester.
- Victoria University of Manchester
- Date:
- 1874
Licence: Public Domain Mark
Credit: Essays and addresses / by professors and lecturers of the Owens College, Manchester. Source: Wellcome Collection.
Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.
107/576 page 87
![HI.] Meteorological Connexion between the Sun and the Planets. 32. Having thus given a short description of what takes place on the sun's surface, let me now say a few words about the connexion between this and that which takes place on the surface of our earth. I have spoken about two kinds of solar storms, ■minor and major. We have, in the first place, the universally distributed mottled surface, which repre- sents the minor storm ; while the sun-spot, which is confined to those regions around the solar equator, may be taken to represent the solar hurricane or cyclone. Now, sometimes there are a great many such spots on the surface of the sun, while, at other times, there are very few, or even none at all. We are indebted for our knowledge of this fact to Hofrath Schwabe, a most persevering German observer, who mapped the sun's surface every day on which it was visible during the long space of forty years. Table I. (page 88) embodies the results of his observations, giving the number of new groups of spots which have broken out on the sun's surface year by year. From this we may see that the yearly number of these groups is by no means regular, but that, on some years, we have very few, while, on other years again, we have a great many. There are certain years of minimum sun- spots when the numbers are smaller than those on either side, and certain other years of maximum sun- spots when the numbers are greater than those on either side.](https://iiif.wellcomecollection.org/image/b21727910_0107.jp2/full/800%2C/0/default.jpg)
