INTRODUCTION.

Most of us, on leaving school or college, are anxious about our future career in the world, and concerning how we are to live, and what will be our occupations. Some young people who have finished their education, find themselves in comfortable circumstances, and are apt to look forward to an easy life; but the majority have a hard struggle before them, ere they can hope to be free from cares and to be successful. Yet it usually happens, that those youths starting with the very best prospects, do not live so happily, usefully, and well, as those who have to struggle with poverty, and who casting aside inglorious ease, labour on perseveringly. It is hard to believe, until the experience of years brings its very practical proofs that knowledge is more valuable than money; and therefore, how to get rich, is a predominant question with the majority of us. But the history of the struggles and successes of some of the men who have led most useful and beautiful lives, generally shows that industry, perseverance and contentment have served them better than pecuniary wealth, and that this has often been a source of trouble to them. There is no better incitement to a youth who has tried to do his best at school, and who is thinking about leading a useful, successful life, than to read the history of the lives of the men whose names are household words in the branches of knowledge he has learned.

At the present time, much care is taken to instruct young people about the nature and uses of plants, the characteristics of animals and the ancient history of the earth. Museums are readily visited, and little home collections of plants, insects, birds, and fossils are frequently easily made. Natural history, in all its branches, is easily studied; and as one becomes learned in it, the names of many men, constantly, come before the student as the masters of their respective subjects. Who has not heard of Linnæus, Cuvier, and Lyell? If any young naturalist will read the history of the lives of these great men, he will find much that is very noble in them; he will see that they made their way through great difficulties, by constant and great intellectual labour, and that they led very good, and useful, and happy lives.

It may happen that any one just commencing to study nature, is anxious to make a great discovery and to obtain a great name. The history of the lives of these and other heroes of science, will prove to him, however, that discoveries are not sudden gains of knowledge, but are the result of very slow and gradual accumulation of facts. If he is a real student of nature, he will strive for truth and not for personal distinction; and the truth, brings a better reward than the fleeting praise of man. The true lasts. He will be able to glean that the special gifts of men, if properly fostered and cultivated, advance knowledge in particular directions, and that certain great changes and advances in the method of learning, have been due to men who have begun poor, have laboured hard, have been persecuted and vilified, and who have nevertheless lived happily in their consciences, and have often become great men in every respect.

The following chapters contain the history of the lives of some of the most interesting men of ancient and modern times—of men who are the heroes of Botany, Zoology, and Geology, and who have added methods of study and many facts to their sciences.