of the canals. This method brings to mind the cultivation of wheat in Lower Egypt, and these prolonged inundations diminish at the same time. the abundance of the parasitical herbs which mix with the harvest at reaping, and of which a part has unfortunately past into America with the European grain.

The riches of the harvests are surprising in lands carefully cultivated, especially in those which are watered or properly separated by different courses of labour. The most fertile part of the table-land is that which extends from Queretaro to the town of Leon. These elevated plains are thirty leagues in length by eight or ten in breadth. The wheat harvest is 35 and 40 for 1, and several great farms can even reckon on 50 or 60 to 1. I found the same fertility in the fields which extend from the village of Santiago to Yurirapundaro in the intendancy of Valladolid. In the environs of Puebla, Atlisco, and Zelaya, in a great part of the bishoprics of Michoacan and Guadalaxara, the produce is from 20 to 30 for 1. A field is considered there as far from fertile when a fanega of wheat yields only, communibus annis, 16 fanegas. At Cholula the common harvest is from 30 to 40, but it frequently exceeds from 70 to 80 for 1. In the valley of Mexico the maize yields 200 and the wheat 18 or 20. I have to observe that the numbers which I here give have all the accuracy which can be desired in so important an object for

the knowledge of territorial riches. Being eagerly desirous of knowing the produce of agriculture under the tropics, I procured all the information on the very spots; and I compared together the data with which I was furnished by intelligent colonists, who inhabited provinces at a distance from one another. I was induced to be so much the more precise in this operation, as from having been born in a country where grain scarcely produces four or five for one, I was naturally more apt than another to be disposed to suspect the exaggerations of agriculturists, exaggerations which are the same in Mexico, China, and wherever the vanity of the inhabitants wishes to take advantage of the credulity of travellers.

I am aware that on account of the great inequality with which different countries sow, it would have been better to compare the produce of the harvest with the extent of ground sown up. But the agrarian measures are so inexact, and there are so few farms in Mexico in which we know with precision the number of square toises or varas which they contain, that I was obliged to confine myself to the simple comparison between the wheat reaped and the wheat sown. The researches to which I applied myself during my stay in Mexico gave me for result, communibus annis, the mean produce of all the country at 22 or 25 for 1. When I returned to Europe I began again to entertain doubts as to the precision of this im

portant result, and I should perhaps have hesitated to publish it, if I had not had it in my power to consult on this subject quite recently and in Paris even, a respectable and enlightened person who has inhabited the Spanish colonies these thirty years, and who applied himself with great success to agriculture. M. Abad, a canon of the metropolitan church of Valladolid de Mechoacan, assured me, that from his calculations the mean produce of the Mexican wheat, far from being below twenty-two grains, is probably from 25 to 30, which, according to the calculations of Lavoisier and Neckar, exceeds from five to six times the mean produce of France.

Near Zelaya the agriculturists showed me the enormous difference of produce between the lands artificially watered and those which are not. The former, which receive the water of the Rio Grande, distributed by drains into several pools, yield from 40 to 50 for 1; while the latter, which do not enjoy the benefit of irrigation, only yield fifteen or twenty. The same fault prevails here of which agricultural writers complain in almost every country of Europe, that of employing too much seed, so that the grain choaks itself. Were it not for this the produce of the harvests would still appear greater than what we have stated.

It may
be of use to insert here an observation*

*Sobre la fertilidad de las tierras en la Nueva España por Don Manuel Abad y Queipo, (MS. note.)

made near Zelaya by a person worthy of confidence, and very much accustomed to researches of this nature. M. Abad took at random, in a fine field of wheat of several acres in extent, forty wheaten plants (triticum hybernum); he put the roots in water to clear them of all earth, and he found that every grain had produced forty, sixty, and even seventy stalks. The ears were almost all equally well furnished. The number of grains which they contained was reckoned, and it was found that this number frequently exceeded a hundred and even a hundred and twenty. The mean term appeared ninety. Some ears even contained a hundred and sixty grains. What an astonishing example of fertility! It is remarked, in general, that wheat divides enormously in the Mexican fields, that from a single grain a great number of stalks shoot up, and that each plant has extremely long and bushy roots. The Spanish colonists call this effect of the vigour of vegetation el macollar del trigo.

To the north of this very fertile district of Zelaya, Salamanca, and Leon, the country is arid in the extreme, without rivers, without springs, and presenting vast extents of crusts of hardened clay (tepetate), which the cultivators call hard and cold lands, and through which the roots of the herbaceous plants with difficulty penetrate. These beds of clay, which I also found in the kingdom of Quito, resemble at a distance banks of

rock destitute of every sort of vegetation. They belong to the trappish formation, and constantly accompany on the ridge of the Andes of Peru and Mexico the basaltes, the grünstein, the amygdaloid, and the amphibolic porphyry. But in other parts of New Spain, in the beautiful valley of Santiago, and to the south of the town of Valladolid, the decomposed basaltes and amygdaloids have formed in the succession of ages a black and very productive earth. The fertile fields which surround the Alberca of Santiago bring to mind the basaltic districts of the Mittelgebirge of Bohemia.

We have already described*, when treating of the particular statics of the country, the deserts without water which separate New Biscay from New Mexico. All the table-land which extends from Sombrerete to the Saltillo, and from thence towards la Punta de Lampazos, is a naked and arid plain, in which cactus and other prickly plants only vegetate! The sole vestige of cultivation is on some points, where, as around the town of the Saltillo, the industry of man has procured a little water for the watering of the fields. We have also traced a view of Old California†, of which the soil is a rock both destitute of earth and water. All these considerations concur to prove what we have advanced in the preceding