Switzerland, thus bounded on the south, is walled in along the entire northern frontier by the range of the Jura mountains, whose loftiest point, the Le Reculet, is five thousand six hundred and twenty-seven feet above the sea level. The mountains of Savoy stretch along the left bank of the Lake of Geneva. Mont Pilatus, the Rigi, and other noted hills of tourists, occupy the eastern central division of the country, among which are situated the largest cluster as well as the most celebrated of the lakes. The great valley of Switzerland, the territory proper of the cantons Vaud, Fribourg, Berne, and Soleure—within which lie all the principal towns, those of the old Roman and all of modern times—forms an extended plateau or basin, inclosed by an amphitheater of mountain land, diversified at intervals by low swelling ridges, undulating hills, precipitous ravines, the deep-set channels of turbid streams, and lovely lakes imbosomed in orchards, vineyards, and meadows of the most luxuriant pasturage. The two great rivers, embracing the entire drainage of the country and of all the lakes, debouch through narrow gorges at opposite sides of the Swiss territory, and pursue, nearly at right angles to each other, their respective courses until they mingle their waters—the one in the Mediterranean, and the other in the Northern Ocean. The little town of Neufchâtel, so often alluded to, lies on the north bank of the lake of the same name, the Jura mountains gently sloping up behind. In the suburbs, forming one of a row of detached unpretending houses, is situated the neat château of M. Agassiz in the middle of a small garden, which rests against the hills, and is bounded on the south by the waters of the lake. A most fitting habitation for the great ichthyologist, surrounded as it is with the noblest scenery, and replete in every locality with the richest treasures of his favorite study. I visited the place in the autumn of 1846, unfortunately when M. Agassiz had just left for America: in a beautiful evening strolled through the garden and adjoining inclosures, and was pleased to observe numerous traces in the rocks, and in some fossil relics lying about, of his studies and researches.