pools, or vault from the drier ridges a few inches into the air. Were the trilobites of the Silurian system,--at one period, as their remains testify, more than equally abundant,--creatures of similar habits? We have at length arrived at the tall sandstone precipices of Dunnet, with their broad decaying fronts of red and yellow; but in vain may we ply hammer and chisel among them: not a scale, not a plate, not even the stain of an imperfect fucoid appears. We have reached the upper boundary of the Lower Old Red formation, and find it bordered by a desert devoid of all trace of life. Some of the characteristic types of the formation re-appear in the upper deposits; but though there is a reproduction of the original works in their more characteristic passages, if I may so speak, many of the readings are diverse, and the editions are all new. It is one of the circumstances of peculiar interest with which Geology at its present stage is invested, that there is no man of energy and observation who may not rationally indulge in the hope of extending its limits by adding to its facts. Mr. Dick, an intelligent tradesman of Thurso, agreeably occupies his hours of leisure, for a few months, in detaching from the rocks in his neighborhood their organic remains; and thus succeeds in adding to the existing knowledge of palaeozoic life, by disinterring ichthyolites which even Agassiz himself would delight to figure and describe. Several of the specimens in my possession, which I owe to the kindness of Mr. Dick, are so decidedly unique, that they would be regarded as strangers in the completest geological museums extant. It is a not uncurious fact, that when the Thurso tradesman was pursuing his labors of exploration among rocks beside the Pentland Frith, a man of similar character was pursuing exactly similar labors, with nearly similar results, among rocks of nearly the same era, that bound, on the coast of Cornwall, the British Channel. When the one was hammering in "Ready-money Cove," the other, at the opposite end of the island, was disturbing the echoes of "Pudding-Gno;" and scales, plates, spines, and occipital fragments of palaeozoic fishes rewarded the labors of both. In an article on the scientific meeting at York, which appeared in "Chambers' Journal" in the November of last year, the reading public were introduced to a singularly meritorious naturalist, Mr. Charles Peach,[9] a private in the mounted guard (preventive service), stationed on the southern coast of Cornwall, who has made several interesting discoveries on the outer confines of the animal kingdom, that have added considerably to the list of our British zoophites and echinodermata. The article, a finely-toned one, redolent of that pleasing sympathy which Mr. Robert Chambers has ever evinced with struggling merit, referred chiefly to Mr. Peach's labors as a naturalist; but he is also well known in the geological field. CHAPTER XII.