What do you mean by light rays?

Spirit-lives are no different from the doctors on earth. 

Their methods of treatment, of course, are entirely different. 

They use materials and forces, which earth doctors do not possess. 

They belong purely to the spirit world.

Spiritual materials are always freshly compounded. 

By their experiments and knowledge, they know what colour—or blend to use, and so their medicaments are in their right proportions. 

Another part of their method of treatment is by light rays—the force is really in the rays themselves.

Spirit-lives can direct these light rays on to any area and in any width they wish—from a broad beam to a small ray. 

It depends upon the nature of the trouble they are working on.