ART. I. A Description of the Western Islands of Scotland, including the Isle of Man; comprising an account of their Geological Structure, with remarks on their Agriculture, Scenery, and Antiquities. By JOHN MACCULLOCH, M. D............. 255 II. A Sicilian Story, with Diego de Montilla, and other Poems. By BARRY CORNWALL.................. III. A Treatise on Adulterations of Food, and Culinary Poisons; exhibiting the fraudulent sophistications of Bread, Beer, Wine, Spirituous Liquors, Tea, Coffee, Cream, Confection- ary, Vinegar, Mustard, Pepper, Cheese, Olive Oil, Pickles, and other Articles employed in Domestic Economy; and Methods of detecting them. By FREDERICK ACCUM, Operative Chemist, Lecturer on Practical Chemistry, Mi- neralogy, and on Chemistry applied to the Arts and Manu- factures; Member of the Royal Irish Academy, Fellow of the Linnæan Society, Member of the Royal Academy of Sciences, and of the Royal Society of Arts of Berlin, &c. &c.......... V. Travels in Italy, Greece, and the Ionian Islands, in a Series of Letters, descriptive of Manners, Scenery, and the Fine 276 ART. VI. 1. Observations, Anecdotes, and Characters of Books and VII. The Life of William Lord Russell, with some Account of SEL.. PAGE 332 ....... 343 MONTHLY LIST OF NEW PUBLICATIONS..................366 प LITERARY AND SCIENTIFIC Information of Works in the Press, or preparing for Publication....... 369 THE EDINBURGH MONTHLY REVIEW. MARCH, 1820. ART. I.-A Description of the Western Islands of Scotland, including the Isle of Man; comprising an account of their Geological Structure, with remarks on their Agriculture, Scenery, and Antiquities. By JOHN MACCULLOCH, M. D. 3 Vols. 8vo. Constable & Co. Edinburgh, 1819. THE HE study of geology, taken in its widest sense, comprehends three separate pursuits, namely, an accurate knowledge of simple minerals; an acquaintance with the actual distribution and arrangement of rocks, as composing what is called the crust of the earth; and, lastly, such inferences, from the facts embraced by the two former, as would lead, in the way of scientific reasoning, to a discovery of the natural causes employed by Divine Wisdom in forming and organizing the materials which enter into the composition of this terraqueous globe. Mineralogy is no doubt a separate, independent science; and might, like botany or zoology, be studied simply on its own account, and without any reference to geological speculations: and, indeed, we find, that precious stones were an object of attention both among lovers of wisdom and lovers of magnificence, and had even been classed and described with no inconsiderable precision, long before they were thought of as affording the means to ascertain what agents had been employed in their formation, and more particularly in that of the rocky bodies, with which they were usually found associated. The lapidary and the florist naturally appear before the botanist and the mineralogist; inasmuch as mankind are guided by their senses to exter nal qualities, long before they are induced, by scientific considerations, to search out those more general properties upon which classification is founded. Surveying and mapping constitute the next stage of advancement in the progress of geology. But neither is this branch of mineral knowledge necessarily connected with theoretical views as to the structure of the earth; for the successful operations of the miner, the agriculturist, and even of the architect, have a very close dependence upon the stoney substances which compose the surface, or, at least, those parts immediately under the surface of the ground where the materials of their several arts are lodged. The riches of a country cannot be known until a mineral survey has been made, setting forth the nature of the rocks which compose its mountains and hills, as well as the subsoil which characterizes its plains and valleys; for although a common statistical report may inform us what is actually done in any particular district, whether on the ground or under it, nothing short of a mineralogical survey can satisfy us as to the capabilities of any portion of our territory, or, in other words, the amount of the wealth which capital and skill might derive from it. But leaving mining and building entirely out of the question, we make bold to assert, that, even in the department of agriculture, it is of more consequence to know the qualities of the rock upon which a soil rests, than the condition of the soil itself at any given period; for as the latter is made up of the former, and is in most cases maintained by it, a minute examination of the stoney subsoil will reveal to the intelligent farmer, how far he is to rely upon nature, and how much he will have to supply by art. In an age, therefore, like the present, which justly boasts that theory and practice were at no time more closely united, nor more effectually aided each other, it is only surprising that mineral surveys are so little encouraged, both by large land owners, and by the public. It is impossible but that much good would be done by means of them; and under this impression, we were much gratified to receive a work of the description in question, written by so able a chemist, and so assiduous a geolo gist, as Dr. Macculloch. The field, indeed, in which he has ex ercised his industry, is not very propitious to improvements in any of the arts connected with landed property; but the facts which he has brought to light, and the principles which these facts have enabled him to explain, admit of an easy application, much beyond the range of his actual researches. The third branch of geology, in the large acceptation of the word, respects, as is well known, the opinions which have been entertained relative to the nature and the mode of operation, of the physical causes employed by the great Creator in forming and distributing the rocky bodies which constitute the shell of the earth. This inquiry, which, if it should be entered up n at all, ought unquestionably to come the last in order, has notwithstanding generally taken the lead; and many an ingenious speculation has been put forth by authors on geology, and by authors of eminence too, who did not know granite from green-stone, nor quartz from obsidian. The theories of Burnet, of Whiston, and of Buffon, were got up at very little expence of mineralogical knowledge; and even the latest and most approved authorities on this subject have pushed their conclusions a great way beyond their actual acquaintance with nature; assuming a uniformity in the collocation of strata, and giving a generality to their doctrines in the relation and succession of different rocks, which a more extensive comparison of facts has, in many cases, compelled them to retract. Dr. Hutton, although a man of great inquisitiveness and ingenuity, had made but small acquirements as a mineralogist when he wrote his celebrated theory; and even of Werner it has been remarked, that he was too hasty in concluding, that all the mountains in the world were formed exactly like the mountains of his native Saxony. Between Hutton and Werner, it is true, there can be no comparison in point of mineralogical knowledge; the former being a mere amateur, whilst the latter possessed all the accomplishments in that department, which science, and long practice in the details of mining, could secure for a man enthusiastically bent upon a favourite pursuit. We, therefore, mean nothing more by coupling their names together than to intimate our opinion, that he who knew most did not know enough to warrant the generalizations upon which his doctrines are founded; and, consequently, that the speculations of the other are proportionally more destitute of that species of proof which alone can give any value to conclusions which must ultimately be determined by an appeal to facts. The world is fast becoming wiser as to the objects and authority of geological science; and ingenious men are no longer allowed to write theories of the earth, as young ladies write novels; that is, entirely from their own imagination or wishes how things should be. On the contrary, an author in this line now finds himself compelled to walk over half the globe, with a hammer in his hands, and a few chemical tests in his pocket, before he can be allowed to give his opinion as to the physical process by which its structure has been accomplished; and, even then, he must speak very guardedly about the other half which he has not personally visited, leaving room in his theory for exceptions and contradictions, which may afterwards be brought to light by |