Many people, however, might find this too great a strain, for it is possible to be worried and tired at the same time, as we all know. Yet there are many hobbies which demand a certain amount of concentration without making too great a call on the mental faculties. They may take up books on travel, for instance, and there is no more fascinating form of reading. Let them select some particular country, and read all they can find about it, its inhabitants and customs, until they are authorities on that subject. Or they may go in for history, studying some particular period, and read all the manuals and historical novels dealing with it. Continuity is a great point in any hobby; it makes it not only more interesting, but there is the pleasure of knowing it is always there, waiting for them, without their having to consider what to take up next. Or they may dip into such subjects as astronomy, botany or a host of others. And these will do more than refresh the mind at the time. People of a worrying disposition are always restless and fidgety on a railway journey, but those who take an interest in such things as geology, flora and fauna will find plenty to occupy their minds with as they go along. Even railway embankments may be made a cinematograph of delight to the man who has studied land formations. And anyone who is interested in architecture need never fear the tedium of having to spend an hour or two in a strange town waiting for the next train. Those who have a taste for poetry may consider themselves fortunate, for there is something in the harmony of words that has a specially beneficial effect on the worried mind. The rhythm, either of blank verse or rhyme, is excellently adapted for reducing the aimless wandering of an overwrought mind to a regular, steady running. Especially is this the case if people take the trouble to learn it by heart. For this acts as a kind of mental mastication, and the poetry is consequently absorbed and becomes a part of their very being. Then they are laying up for themselves a store of treasures which they may enjoy at any moment. People who worry are always liable to be irritable when alone, and need something to counteract their moody tendencies.