When required for reading, both rollers are fixed in a stand, and slowly moved by clockwork, which spreads before the eyes of the reader a length of about four inches at once.

The motion is slackened or quickened at the reader's pleasure, and can be stopped altogether, by touching a spring.

Another means of reproducing, not merely writings or drawings, but natural objects, consists in a simple adaptation of the _camera obscura_.

[The only essential difference from our photographs being that the Martial art reproduces colour as well as outline, I omit this description.] While I was practising myself in the Martial language my host turned our experimental conversations chiefly, if not exclusively, upon Terrestrial subjects; endeavouring to learn all that I could convey to him of the physical peculiarities of the Earth, of geology, geography, vegetation, animal life in all its forms, human existence, laws, manners, social and domestic order.

Afterwards, when, at the end of some fifty days, he found that we could converse, if not with ease yet without fear of serious misapprehension, he took an early opportunity of explaining to me the causes and circumstances of my unfriendly reception among his people.
"Your size and form," he said, "startled and surprised them.