THE NATURAL HISTORY OF COMMERCE.*

Tars somewhat obscure title has been assigned to a volume describing what is generally known as " raw produce." The origin, uses, and value of most of the useful and ornamental materials derived from the animal, vegetable, and mineral kingdoms are given in Dr. Yeats' volume. The subjects which it includes are treated in a similar manner in several of the official catalogues of the South Kensington Museum, in Johnston's Chemistry of Common Life, and in the various technological works of Professor Archer and Mr. P. L. Simmonds. These books, together with many articles scattered in periodicals, as well as Customs and Imports Returns, might seem to be capable of furnishing excellent and abundant information concerning all the topics of the volume now under notice. This, however, is not the case ; indeed, few literary tasks are as difficult as the production of ..a really sound treatise on the raw materials of manufactures. Let us look for a moment on the complexity of the subject. We require the aid of the zoologist, the botanist, and the geologist to tell us the character of the animal, or plant, or mineral from which each particular sort of material is derived. Then we should add some details concerning the seasons and modes of collecting or obtaining these materials, with notes as to the treatment which they may undergo before they reach the manufacturers' hands. Further, we need data as to the amount, value, and consumption per annum of the materials raised, imported and manufactured. And finally, we must have presented to us an exact if simple outline of the processes of manufacture themselves, as well as of the nature and uses of the products obtained. It will readily be understood that no one author can possibly possess the know- ledge and judgment essential to such a task as that we have just now sketched. It will not be surprising there- fore to find that Dr. Yeats' volume is certainly amenable to criticism. Our author has been assisted in the preparation of the Natural History of Commerce, by several friends, yet in spite of their help, errors in matters of fact are by no means infrequent. While acknowledging the value of the plan of the book, we feel bound to point out those particulars in which the execution of the plan admits of improvement. We object, for instance, to a general vagueness of expression which pervades the volume. The con- stant recurrence of such expressions as "immense quantities," ",vast tracts," " insignificant numbers," &c., indicates a lack of accurate thought and of care for exact detail. Again, we notice that the commercial statistics are often quite out of date. For instance, the only information as to the imports of opium into the United Kingdom is that nineteen years ago fifty-one tons were received, principally from the Eaat Indies and Turkey. The omis- sion of several most important commercial products cannot be passed over in silence. Why is no mention made of oilcakes so extensively used for feeding cattle, or of such important plants as meadow grasses and clovers, or of roots such as the turnip and the carrot ? Of other defects in the volume before us we shall have occasion to speak in giving, as we now proceed to do, an_abstract of its scope and contents.

There are four parts in Dr. Yeats' volume. The first section is chiefly occupied with an account of the geographical distribution of " raw produce," and its bearings on the economy of nations.

Our national home is described in chapter ii. " The United Kingdom," we are told, " comprises several hundred islands, of which Great Britain and Ireland are the chief, the remainder being relatively unimportant" (p. 9). This appears to be a fresh, if not instructive way of looking at the United Kingdom, and reminds us of a story assigned to the minister of a microscopic island in the firth of Clyde, Little Cumbrae, who prayed the Lord to have mercy on the sinners in the neighbouring island of Great Britain.

The relations of geology to agriculture are noticed in chapter iii., which is curiously entitled "The Effects of Geology on Agrical- tire " in one place, and in another "The Effects of Geology onthe In- dustry of the British People." We are sorry to say that the agri- cultural chemistry of this part of the volume is of the weakest de- scription. (p. 36). Two pages further on we find a chemical and agricultural comparison of the capabilities of the inferior oolite,

* The Natural Ilistory of Commerce. By J. Yeats, LL.D. London : Cassell. 1870 the great oolite and the cornbrash. It is to be regretted that a fundamental error underlies this apparently instructive comparison.

The composition of these rock strata is given to show the variations, in the important ingredients of sulphate of lime and phosphoric acid which mark them. Unfortunately these rocks have had very

little to do with the formation of the soils now resting on them. Some of the Cotteswold soils, for example, do not contain one per cent. of lime, though resting on rocks containing more than 90. It will thus be evident that the composition of the subjacent rock is no sure guide to the determination of the fertility of the soil above,

its productive power in bushels of wheat, or its rental. (pp. 38, 39). Chapter ix. of the first part introduces the subject of the inter- change of raw produce. The peculiarities of the " wine and oil '" countries and of those distinguished by their considerable produc- tion of beer and butter are duly noted. The next two chapters.

discuss briefly the characteristics of Asian and American pro- duce ; while the last chapter of this part is occupied by the deeply interesting subject of the changes caused on the earth by the various workings of natural change or of human power and intelligence. A brief citation may be- here made from this chapter, showing how human agency may modify, unintentionally or otherwise, the aspects of nature.

" Mr. Grierson, at the meeting of the British Association in 1866„ read a paper referring to the destruction of plantations at Drum- lanrig in Dumfriesshire by the voles, often called rats, which are the pest of Sweden. They appear to be migratory in their habits, and occasionally increase in myriads. From the recent slaughter of rapacious birds, such as owls, hawks, and eagles, which nature has appointed to bound the unlimited fecundity of the rodentia, the voles have found a safe field of action. They principally destroy the young oak and ash, gnawing a ring of bark near the roots and beneath the grass, the trees being unable to resist such, attacks until after at least twelve years' growth."

The second part is entitled "The Commercial. Products of the Vegetable Kingdom." It is divided into two sections, one refer- ring to food plants, the other to industrial and medicinal plants.

The various kinds of corn plants are first described, then the leguminous seeds. Plants distinguished for the production of special varieties of starch, such as arrowroot, tapioca, and sago, come next in order. Spices and condiments follow. Of plants. yielding sugar, more should have been said about the sugar-beet, which is dismissed in a line or two. We find described among the food plants those which are useful in the preparation of nutritious. and stimulating beverages, such as tea, coffee, wine, and beer. Plants, the fruits, leaves, or roots of which are eaten, conclude this section, before leaving which, we stop to protest against the statement (p. 192) that carrageen, or Irish moss (a species of sea- weed), "contains an abundance of gelatine." It contains a large proportion of a substance allied to starch, and becoming muci- laginous when boiled. The absence of nitrogen from this mucilage, producing substance is sufficient to prove that it has no connection whatever with gelatine. We must also contradict the statement on page 188 that the Brazil nut is also called the Monkey-pot> which is really the produce of quite another tree, the Lecythis olearia, the seeds of which are known as Sapucaya nuts.

Industrial and medicinal plants are very numerous. We cannot stop to refer to the plants yielding fibres fit for textile fabrics,. dyeing materials, balsams, gum and resins, building and furniture woods, medicinal preparations, narcotic products, and the thou.sancl and one other materials which members of the vegetable kingdom, all over the globe furnish to trade and the arts. One mistake in the paragraphs on oils strikes us as we write. Dr. Yeats states (p. 202). that the oil of lavender is obtained from Lavandula spicata, raised in large quantities at Mitcham in Surrey, but that the oil is also imported from France and Germany. The English oil of lavender, which is more costly and much more exquisite in fragrance than the foreign, is obtained from L. vera. The foreign oil is distilled from L. spicata, and is often termed oil of spike. On p. 233 our author introduces us to a new personage, the " Countess of Cinchona." The lady after whom Peruvian bark received its botanical name, Cinchona, or more correctly, Chin- chona, was the Countess of Chinchon, " wife of the viceroy of Peru, who in 1638 was cured of intermittent fever by its use." Although the botany of this part of the work is generally correct, an occasional slip may be noticed. On p. 227, for instance, the

banyan tree, Ficus indica, is wrongly spoken of as one of the plants yielding indiarnbber, and is named F. elastica. The chemistry of plant-life is also occasionally incorrectly given. The statement (p. 139) " that starch is changed by oxygen into a sugary gum called diastase" is wholly devoid of foundation. Starch cannot yield diastase, which is, moreover, not a sugary gum,

but a nitrogenous ferment, characteristic of malt and germinating seeds, and capable of turning starch into gum and sugar.

Part III. is devoted to the commercial products of the animal kingdom. Here the zoological classification is thoroughly out of date. We need only mention the fact of the sub-kingdom of the Radiata being retained by our author, to indicate to any naturalist the truth of our assertion. Furs are treated with considerable detail among - mammalian products, and furnished during the recent wintry wea- ther a congenial subject of study. The disagreeable so-called per- fumes derived from animals, and known as musk, civet, castoreum, and ambergris, are next discussed. Animal oil and fat, wool, leather, hair and bristles, horns and ivory, edible nests, feathers, quills, such are a few of the materials described among the products of mammals and birds. Reptiles yield the turtle so esse ntial to the proper nutrition of aldermen, and tortoise-shell, which has been applied to many decorative and useful purpo ses. Among the fish, mention is made of the whitebait, which is now ascertained to be the fry of the sprat. Same persons may regret to learn that the sprat itself is sometimes taken in such overwhelming quantities in the Thames' estuary as to be sold for manure at 6d. a bushel. Forty bushels furnish an adequate dressing for one acre. We have not space to do more than just refer to the notices of pearls, leeches, lobsters, bees, corals, and sponges. (pp. 330 et seq.) A fourth part, relating to raw mineral produce, concludes the natural history of commerce. A few pages about metals are followed by notes on coal, limestones, sands, clays, common saline substances, and precious stones.

We have already pointed out with some detail the nature of the defects which, in our opinion, mar the usefulness of the book before us. It is right to add here that it contains a great number of interesting facts about natural objects, and that these facts have been collected with considerable trouble and arranged with care.