These desirable features are obtained by the use of an elastic rubber joint, the case itself being built of steel, but all the joints closed with this soft elastic rubber, on the same principle as a rubber gas tube is connected with a fixture. This case, to look at, is very compact and solid, but it can be almost instantly separated, either for changing sprockets, getting at the chain, or removing rear wheel. The operation is very brief, and even that has to be gone through with seldom a change of tires or renewal of broken spokes being almost the only occasion for separating the case. The chain can be taken out if desired, but as a matter of fact one always forgets that there is a chain when riding the “Enclosed Chain Model,” as this construction is now called.
CHAPTER VI.
THE CHAIN AND ITS FUNCTIONS.
There are few, if any, parts of the modern bicycle that have played a more important rôle in its development, than has the chain, and yet it is safe to say that there is no part of the vehicle to which the average rider pays less attention, save to occasionally clean it of its accumulated impediments, or which he understands so little.
BROWN
ROLLER SPROCKET.
Every rider, of course, understands how important is the office of the chain in the propulsion of his wheel—that without it his machine is an utterly useless structure of metal, wood and rubber. As to its parts, however, and their relation to one another, he is oftener than not carelessly indifferent. While as to the mechanical skill and genius that has overcome, one by one, the past difficulties of chain and sprocket propulsion, as applied to the bicycle, bringing it in the end, to its present state of perfection, he is wholly uninformed. Many riders have been inconvenienced and annoyed to the extent of exasperation, upon discovering that “something was wrong” about their wheels. Just what, they have been utterly at a loss to tell or understand, but the fact has remained that “something was wrong,” and so, cutting their rides short, they have despatched their wheel forthwith to the repair shop. Had they known, as the repair man knew, that it was their own lack of familiarity and consequent sense of appreciation of that apparently simple, yet sensitive part of their machines—the chain, to which their misfortunes were due, how great would have been their astonishment.