Lecture Vi.

STARS.

We try to make a Map--The Stars are Suns--The Numbers of the Stars--The Clusters of Stars--The Rank of the Earth as a Globe in Space--The Distances of the Stars--The Brightness and Color of Stars--Double Stars--How we find what the Stars are made of--The Nebulæ--What the Nebulæ are made of--Photographing the Nebulæ--Conclusion 318

CONCLUDING CHAPTER.

HOW TO NAME THE STARS. 381

STAR-LAND.