Heidelberg in the year 1826, at the age of nineteen. It is not easy to make citations from a book of such uniform interest; but his student-life at Heidelberg, and afterward at Munich, as gathered from various passages in this history, has a peculiar fascination. In one of the first acquaintances made by him at this time, Agassiz found a life-long friend—
and in after-years a brother. Professor Tiedemann, by whom he had been so kindly received, recommended him to seek the acquaintance of young Alexander Braun, an ardent student and especial lover of botany. At Tiedemann's lecture, the next day, Agassiz's attention was attracted by a young man who sat next him. and who was taking very careful notes, and illustrating them. There was something very winning In his calm, gentle face, full of benevolence and intelligence. Convinced, by his manner of listening to the lecture, that this was the student of whom Tiedemann had spoken, Agassiz turned to his neighbor, as they both rose at the close of the hour, and said, "Are you Alexander Braun?" "Yes. Are you Louis Agassiz?". . . The two young men left the lecture-room together, and from that time their studies, their excursions, their amusements, were undertaken and pursued together. . . . Braun learned zoölogy from Agassiz, and he in turn learned botany from Braun.
In a letter of young Braun to his parents, written at this time, he says:
In my leisure hours I go to the dissecting-room, where, in company with another young naturalist, who has appeared like a rare comet on the Heidelberg horizon, I dissect all manner of beasts, such as dogs, cats, birds, fishes, and even smaller fry, as snails, butterflies, caterpillars, worms, and the like. . . . I sometimes go with this naturalist on a hunt for animals and plants. Not only do we collect and learn to observe all manner of things, but we exchange views on scientific matters In general.
And he adds, concerning Agassiz's attainments at this time:
I learn a great deal from him, for he is much more at home in zoölogy than I am. He is familiar with almost all the known mammalia, recognizes the birds from far off by their song, and can give a name to every fish in the water. In the morning we often stroll together through the fish market, where he explains to me all the different species. He is going to teach me how to stuff fishes; and then we intend so make a collection of all the native kinds. Many other useful things he knows; speaks German and French equally well, English and Italian fairly. Is well acquainted with ancient languages. and studies medicine besides. . . . To utilize the interval spent in the time-consuming and mechanical work of preparing specimens, pinning insects, and the like, we have agreed that, while one is employed, the other shall read aloud. In this way we shall go through various works on physiology, anatomy, and zoölogy.
They spent their vacations together; "drew, studied, dissected, arranged specimens, discussed theories with their young brains teeming about the growth, structure, and relations of animals and plants." Another young botanist, Karl Schimper, was taken into this Heidelberg intimacy, and the three were inseparable in their studies. At one time Agassiz was kept at home in Switzerland by sickness, but the letters passing between these fellow-inquirers were remarkable. Here is a set of questions propounded by Agassiz to Braun and Schimper at Heidelberg. He was studying the fishes of the Swiss lakes and trying to catalogue them, and he says:
As I am on the chapter of fishes, I will ask you 1. What are the gill-arches? 2. What the gill-blades' 3. What is the bladder in fishes? 4. What is the cloaca in the egg-laying animals? 5. What signify the many fins of fishes? 6. What is the sac which surrounds the eggs in bombinator obstetricians? [a creature about which there had been former correspondence].
Braun, on his part, writes to Agassiz: "On my last sheet I send some nuts for you to pick, some wholly, some half, others not at all cracked." The following are some of the mooted questions:
1. Where is the first diverging point of the stems and roots in plants, that is to say, the first genicalum?
2. How do yon explain the origin of those leaves on the stem which, not arising from distinct geniculi, are placed spirally, or scattered round the stem?
3. Why do some plants, especially trees (contrary to the ordinary course of development in plants), blossom before they have put forth leaves (elm-trees, willow-trees, and fruit-trees)?
4. In what succession does the development of the organs of a flower take place—and their formation in the bud? (compare campanula, papaver).
5. What are the leaves of the spergula?
6. What are the tufted leaves of pine-trees?
7. What is individuality in plants?
It matters not that most of these problems were solved long ago; they no less illustrate the action of these young minds in carrying forward their fruitful studies. It is to these two botanists, Braun and Schimper, that botany owes the discovery of the law of Phyllotaxis which is hinted at in the first of the above questions. We next find the three friends established at Munich, attending the lectures of Döllinger, Martins, Schelling, Oken, the latter of whom was extremely friendly with them, inviting them once a week to his house,
