From these calculations we deduce some very important facts as to the physical and intellectual condition of Mexico, which are very significant in the illustration of history. It appears that the total number of pure whites in the republic, is, in all probability, not more than 1,100,000; while the Indians, Negroes, Zambos, Mulattoes, Meztizos, and all the mixed bloods, amount to 6,526,831. During our residence in Mexico we ascertained from reliable authority that among the Indians and negroes but two _per cent._ could read and write, while among the whites, and castes, but twenty _per cent._ were estimated to enjoy those benefits. Thus we have: 87,229 Indians and Negroes able to read and write. 653,069 Whites and mixed castes able to read and write; or, only seven hundred and forty thousand, two hundred and ninety-eight individuals, either completely educated or instructed in the simplest rudiments, out of a population of more than seven and a half millions. These are startling statistics in regard to the citizens of a nation whose government is theoretically and practically based on the culture of the people or their capacity for self-rule; and, when considered in connexion with the historical details presented in the first volume of this work, they will show that the distracted condition of Mexico is a mingled cause and consequence of her intellectual darkness.[7] One of the most interesting investigations in Mexican statistics would be to compare the number of births in the regions called the _tierras calientes_--or hot country, with those in the tierras frias, or _cold region_. From calculations made by Cortina in 1838, from data derived from nine departments, he concluded that the excess of births in the warm regions or _tierras calientes_ was 1-5/10 per 100, over the _tierras frias_. He gives the following actual statistics in evidence: 1st. Result of the general census of the department of ZACATECAS since the year 1824, and progressive increase of population therein before the separation of the portion of Aguas Calientes:-- Years. Total population. Increase of population biennially. 1824 247,295} 1826 272,901} 25,606 1828 274,537} 1,636 1830 290,044} 15,507 1832 314,121} 24,077 1834 331,781} 17,660 2d. In 1836, after the separation of the portion of Aguas Calientes, this department had 264,505 inhabitants. In June, 1838, it had 273,575 " ------- Increase in one year and a half, 9,070 3d. In the period from 1st of January, 1837 to 30th of June, 1838, there were born in the said department, 21,941