earthenware, paper, coral beads, Brazil-wood, and Mexican dollars.

The exports are sweet almonds, bitter almonds, gum-Barbary, gum-Soudon, gum-sandrac, beeswax, goat-skins, oil of olives, sheep's wool, ostrich-feathers, elephant's teeth, pomegranates, raisins, wormseed, rose-leaves, glue, fennel, walnuts, cummin-seeds, lead-ore, capers, carraway-seeds, and similar productions. The total value of imports for one year was 151,4501., and of exports, after paying freight and European duties, was 127,6791.; an amount which, though not great, was highly advantageous to the foreign merchant, inasmuch as all the goods conveyed thither were manufactured, while all the commodities received in return consisted of raw produce.*

But besides the commercial transactions now mentioned, Morocco, like the other Barbary States, maintains a constant intercourse with the negro nations beyond the Sahara, whence are brought gold-dust, ivory, and gums, more especially that valuable species which is known by the name of gum-Senegal or Soudon.

At Mogadore, accounts are kept in nutkeels of ten ounces; the ounce being divided into four blankeels, and the blankeel into twenty-four fluce. From their proportion to the Spanish dollar, the blankeel may be valued at 1d., the ounce at 4d., and the nutkeel or ducat at 3s. 4d. As to weights, again, the commercial pound is generally regulated by the contents of twenty Spanish dollars; and therefore 100 pounds Mogadore weight, or the quintal, are equal to 119 pounds avoirdupois. But the market-pound for provisions is 50 per cent. heavier, or one pound twelve and a half ounces avoirdupois. The corn-measures are for the most part similar to those of Spain, though there are considerable discrepances. The principal long-measure is the cubit or canna, equal to twentyone inches English.†

Northern Africa, as has been already suggested, possesses so many physical advantages, and is capable of so vast an improvement, that, were it in the hands of an enlightened people, its commerce would soon rival that of the ancient

* Jackson's Morocco, p. 193.

+ M'Culloch's Dictionary of Commerce, p. 805; and Murray's Encyclopædia of Geography, p. 1200.

Phoenicians, or even of the most successful among modern nations. The country, which was once the granary of Rome, might again afford corn to an immense population, and supply with the richest delicacies of the vegetable kingdom the luxurious inhabitants of Italy, Spain, France, and England. Nor ought the views of an expanding trade to be limited to the lands, fertile as they may be, which stretch from the edge of the Desert to the shores of the Mediterranean. The recent discovery of a river connecting the Atlantic with the interior of the magnificent plains that compose the central provinces of the continent, encourages hopes of civilization, knowledge, and wealth, which at present it might seem romantic to express. The arts of Europe, and the astonishing command over the elements of nature that science continues to confer upon educated man, will enable future colonists to subdue the wildest portions of the globe, and replenish them, too, with nations delighting in the enjoyments of social life, and cultivating those lofty studies which at once bless and adorn the intercourse of human beings.*

* For additional observations on the commerce of the Barbary States, the reader is referred to Pananti's "Narrative of a Residence in Algiers," chap. xviii., p. 245, &c.

CHAPTER XI.

Natural History.

Additional Knowledge of Africa supplied by the French-GEOLOGY-Great and Little Atlas-Structure of the formerSucceeded by Tertiary Rocks-Supposed Extent of the Greater Atlas-Cyrenean Mountains-Reflections on the Desert-Relics of organized Bodies-Transition-rocks-Limestone-Talc-slate-Mineral Species-Secondary FormationLimestone-shales-Marlstones and Sandstone - Imbedded Minerals-Extent of the Little Atlas-Metals - Tertiary Rocks-Calcareous Sandstone, Clays, Porphyry, Dolerite, Greenstone, and Basalt-Blue Marl or London-clay-Organic Remains-Volcanic Rocks-Diluvian Formation-Soil of Metijah-Postdiluvian Formation-Uniform Operation of General Laws-ZOOLOGY-Scorpions and SerpentsBûska Effah-Boah-Locusts-Quadrupeds-HorrehAoudad-Nimmer-Heirie-Camel-Desert-horse-Birds

Ostrich-El Rogr-Tibib-El Hage-Graab el Sahara-Karaburno-Burourou-BOTANY-List of Plants-HashishaEuphorbium-Silphium-Medicinal Qualities-Opinions of Della Cella and Beechey-Reflections.

THE scientific world are indebted to the recent successes of the French arms in Northern Africa for some valuable additions to the knowledge of nature in that interesting portion of the globe. The travels of Dr. Shaw supplied the first collection of facts on which any reliance could be placed, relative to the minerals, animals, and plants of the Barbary States; and had he possessed a more intimate acquaintance with geology, his work would probably have presented so complete a record of physical phenomena as to leave nothing to be accomplished by subsequent writers. It is in respect to this latter department that we are under the greatest obligations to the labours of M. Rozet, the author to whose description of Algiers we have already drawn the attention of the reader.

SECTION 1.-GEOLOGY.

There appears, between the 28th and the 36th degrees of north latitude-the limits to which our observations are meant to be confined-two separate groups of mountains, which are usually distinguished by the names of the Great and the Little Atlas. The former, though it has not been minutely examined by the eye of science, both from its neight and external aspect, may be confidently pronounced to belong to the primitive formation. We are, indeed, assured on a good authority, that the central and higher chains are composed of granite, gneiss, mica-slate, and clay-slate, while the inferior ranges exhibit layers of secondary limestone and sandstone. These deposites abound in organic remains, shells, corals, and even fishes, and are accordingly said to be referrible to the calcareous strata of the secondary class, extending from the lias, or even the magnesian limestone, to chalk inclusive. Resting upon these last, again, are various of the tertiary rocks, among which, at sundry points, are found gypsum and salt-springs. It is added, that the secondary and tertiary formations are, in numerous places, disturbed and upraised by trap-rocks of comparatively modern date.*

The description now given applies to the whole country northward of the Atlas, and agrees in substance with the minuter details furnished by the French engineer. We cannot, however, refrain from observing, that no information is anywhere conveyed as to the termination, on the east or the south, of that lofty mass to which our inquiries are now directed. It has been sometimes supposed that the Alpine range, of which the towering summits are seen from Morocco, extends to the banks of the Nile; or, at least, droops into the Desert near the site of the celebrated Ammonium, at no great distance from the territory of Barca. Others have been willing to trace the continuity of this formation to the neighbourhood of Syene, where mountains of a kindred origin flank the course of the river, and stretch towards the centre of the continent. But it must be admitted, that there is no good ground for either of these conjectures. Della Cella is decidedly of opinion, that the hills of the Cyrenaica

* Article by Professor Jameson, in Murray's Encyclopædia of Geography, p. 1196.

are not a prolongation of that magnificent chain which rises upon the northern border of the African coast, and extends, in the manner already described, from the Great Syrtis as far as the kingdom of Morocco. This, he acknowledges, does not prevent the calcareous constitution of Mount Atlas from forming also the character of the Cyrenean mountains. The hills between Tunis and Algiers are, for the most part, composed of limestone, and are full of shells; and such is the character of the eminences observed by Hornemann in the tract beyond the Barcean Wilderness. But the long space, beginning at these heights and terminating at the granitic mountains on the Nile, whence the Egyptians and Romans drew the enormous stones which they employed in adorning their public edifices, is covered with a level ocean of sand. It appears, therefore, that the system of rocks, to which the ridges of the Cyrenaica belong, has no immediate connexion with the Atlas, properly so called, but rather with that smaller group, denominated the Little Atlas, which, rising to a considerable elevation in some parts of the Algerine and Tunisian States, attains a still nobler altitude in the country of the ancient Pentapolis, and at length finally declines in the Catabathmos towards the land of Egypt. It is also manifest, that the bases of the mountains on this part of the Mediterranean coast are covered, upon their northern borders, with a marine alluvial soil, sometimes decomposed and sandy, and sometimes conglomerated in crusts of different degrees of thickness.*

The mention of the Desert cannot fail to remind the reader, that the consideration of its flat and dreary waste suggests one of the most difficult problems in geology. The numerous relics of organized bodies which must have been produced in the sea, mixed with the remains of forests which probably at one time adorned a variety of hills and valleys now obliterated by sand, seem to afford evidence that the present aspect of Central Africa is not the original one, but ought to be ascribed to some dreadful catastrophe, of which it perpetuates the effects. "Africa," says a late traveller, "has evidently been washed across. It is therefore, he presumes, reasonable to conclude, that the weary plains in the interior, south of the Atlantic range, may have been thus

* Narrative, p. 166.