LOOKING BEYOND THE WORLD. 
139 
In Job, perhaps the oldest book in the world, we 
read: “ Canst thou bind the cluster of the Pleiades, 
or loose the bands of Orion ? Canst thou lead forth 
the Mazzaroth in their season ? or canst thou guide 
the Bear with her train ? ” 
Fig. 70. — From a photograph of the Pleiades. 
In the second century b. c. Ptolemy gave a list of 
forty-eight of these clusters or constellations, to which 
nearly as many more have since that time been added. 
The only value they have is for convenience in locat¬ 
ing comets and planets in their motion. For instance, 
the astronomer says a certain comet, planet, or nebula 
