for them; but I promise you that as soon as the spring opens I will go to work, and you shall have all you want. If, in spite of everything, your hopes are not realized, I shall be very sorry, but rest assured that it is not my fault. . . TO HIS SISTER CECILE. MUNICH, October 29, 1828. . . .I have never written you about what has engrossed me so deeply; but since my secret is out, I ought not to keep silence longer. That you may understand why I have entered upon such a work I will go back to its origin. In 1817 the King of Bavaria sent two naturalists, M. Martius and M. Spix, on an exploring expedition to Brazil. Of M. Martius, with whom I always spend my Wednesday evenings, I have often spoken to you. In 1821 these gentlemen returned to their country laden with new discoveries, which they published in succession. M. Martius issued colored illustrations of all the unknown plants he had collected on his journey, while M. Spix brought out several folio volumes on the monkeys, birds, and reptiles of Brazil, the animals being drawn and colored, chiefly life-size, by able artists. It had been his intention to give a complete natural history of Brazil, but to the sorrow of all naturalists he died in 1826. M. Martius, desirous to see the completion of the work which his traveling companion had begun, engaged a professor from Erlangen to publish the shells, and these appeared last year. When I came to Munich there remained only the fishes and insects, and M. Martius, who had learned something about me from the professors to whom I was known, found me worthy to continue the work of Spix, and asked me to carry on the natural history of the fishes. I hesitated for a long time to accept this honorable offer, fearing that the occupation might withdraw me too much from my studies; but, on the other hand, the opportunity for laying the foundation of a reputation by a large undertaking seemed too favorable to be refused. The first volume is already finished, and the printing was begun some weeks ago. You can imagine the pleasure I should have had in sending it to our dear father and mother before they had heard one word about it, or knew even of the proposition. But I hope the premature disclosure of my secret (indeed, to tell the truth, I had not imposed silence on M. Schinz, not dreaming that he would see any one of the family) will not diminish your pleasure in receiving the first work of your brother Louis, which I hope to send you at Easter. Already forty colored folio plates are completed. Will it not seem strange when the largest and finest book in papa's library is one written by his Louis? Will it not be as good as to see his prescription at the apothecary's? It is true that this first effort will bring me in but little; nothing at all, in fact, because M. de Martius has assumed all the expenses, and will, of course, receive the profits. My share will be a few copies of the book, and these I shall give to the friends who have the first claim.