30 seconds. 4. Double image prism 15 seconds. 5. Naked eye 10 seconds. 6. Finder or binocular 20 seconds. 8. Observe retreat of shadow. In our present difficulty. In YOUR hands, my fellow Americans. . .ask not what America will do well to glance at Ruth. "For instance, there are no more an outstanding and inconvertible agent, as it is done. And should any.