After long and careful research in the great libraries and museums of the world, I have collected a table of brain weights of eminent men, along with which are entered, in my original document, the occupation of the subject, age at the time of determination, and the source whence the item is derived. These can not be given within the limits of this article, and only the briefest and most generalized summary of the main features can be indicated. The largest weight of brain in the whole list is that of the Russian novelist Turgenieff, whose brain weighed, at the time of his death, at sixty-five years of age, 71 ounces.[32] It is a considerable step from him to the next in order, the English mechanician and author, Knight, whose brain weight at the age of fifty-eight was 64 ounces. Then follow the Scottish physician Abercrombie, 63 ounces; General B. F. Butler, 62 ounces; and the Scottish general Abercromby, 62 ounces. Another group of nine, including weights from 58.6 ounces to 54 ounces, includes Jeffrey, Scottish judge and author, Thackeray, Cuvier, George Combe, United States Senator Atherton, Spurzheim, and the Scottish physician Simpson. The next group, 53.6 to 50, is larger, including twenty-one names, among which are Daniel Webster, Agassiz, Napoleon I, the Scottish divine Chalmers, the mathematicians De Morgan and Gauss, the anthropologist Broca, and the generals Skoboleff and Lamarque. The last group, 49.9 to 40 ounces, contains twenty-five names, including those of the philosopher Huber, Grote, Babbage, the anthropologist Bertillon, Whewell,[33] Liebig, Gall, Gambetta, and Bishop, the mind reader. Only one remove from the foot of the list is Gambetta, a man of indisputably high genius and ability, with a brain weighing only 40.9 ounces.[34]
The table goes to illustrate a general rule which I discovered and published several years ago, that larger brains appertain to natives of colder climates. Dr. John Abercrombie, for instance, was born at Aberdeen, Scotland, on the German Sea, and farther north than any part of the United States. Sir Ralph Abercromby was born in the county of Clackmannan, Scotland, where it is far colder than any part of southern Europe. Lord Francis Jeffrey first saw light in Edinburgh. General Butler was born in Deerfield, New Hampshire. Ivan Turgenieff, with the heaviest brain of all, was a native of cold, inhospitable Russia. Dr. Franz Joseph Gall (brain weight 42.2 ounces)[35] was born in Würtemberg, in southern Germany, passed most of his life in Vienna and Paris, and, being a student, spent much of his time indoors. Gambetta was born at Cahors, France, of Italian parents. This climatological view of the size of brains is confirmed by a paper, "Crania," of the Philadelphia Academy of Sciences, which gives as the average size, in cubic inches, of the cranial cavities of various nationalities, taking the results of many measurements: Lapps, 102; Swedes, 100; Anglo-Saxons, 96; Finns, 95; Anglo-Americans, 94; Germans, 92; Celts, 88; Malays, 86; Chinese, 85; Tombs of Gizeh, 84; embalmed Semitic, 82; Egyptians, 80; Fellah, 79; Bengalese, 78.
A table of average brain weights of various nationalities, compiled from Topinard's and Manouvrier's works and other standard anthropological publications, illustrates the same tendency toward greater brain weights in colder countries. One of its results is to show that the colder air of the United States produces larger brains in the negroes than the warm air of Africa. The table further shows, in the comparisons of Hindus and African negroes, that the brains are smallest in the warmest countries, irrespective of race or nation; and that the largest average attained is in Scotland, where it is never extremely warm.
The measurement of the cranial cavity is a very uncertain gauge of the size of the brain, for the cerebro-spinal fluid may occupy a large share of the space. Weighing the brain is without doubt the only scientifically certain method of determining its size and mass.
Perhaps the most remarkable case in the table of great men's brains is that of Gambetta, who was behind none of his compeers in ability, and yet had the smallest brain of all. The first table of the "Average Weight of the Human Body and Mind," compiled from Dr. Boyd's researches among the sane, which was based on more than two thousand post-mortem examinations, gives 45.9 ounces as the average brain weight of boys from seven to fourteen years of age, and 40.2 ounces as that of boys and 40.1 ounces of girls from four to seven years of age. And this little brain of 40.9 ounces appertained to a man, "a lofty, commanding, mental figure, standing out in bold relief from the crowd of mediocrities which he dwarfs and shadows," the embodiment of the French Republic, who steered it through one of its most perilous crises, "the foremost Frenchman of his time," who "established his claim to be placed in the very front rank of European statesmen," and whose untimely death was spoken of as "nothing less than the sudden extinction of a powerful individual force, one of the most powerful, indeed, of such forces hitherto operating in Europe."
In illustration of the association of large brains with small minds, we have compiled from various sources of recognized authority a list of one hundred and twenty-five persons of ordinary or weak minds, idiots, imbeciles, and criminals, whose brains were generally larger than those of the distinguished men subjects of the preceding notes. Of these, Rustan, an ignorant and unknown workman, appears with a brain weighing 78.3 ounces;[36] the dwarfed Indian squaw who follows him, of 73.5 ounces;[37] an illiterate and weak-minded man had a brain of 71.3 ounces;[38] and a congenitally imbecile person cited by Dr. Ireland, with one of 70.5 ounces.[39] Another imbecile cited by Dr. Ireland had a brain of 63.2 ounces, and the brain of an idiot with a large head, eighteen years old, who had an idiotic sister, weighed 62.8 ounces. The brain of the idiot, No. 56 of the men in the table, 59.5 ounces, is exceeded in size by those of only five on the list of famous men, while eleven persons recorded as idiots, imbeciles, and children had brains heavier than his. An idiot boy of fourteen years, very malicious, who never spoke, and who nearly killed his sister with a pick, had a brain weight of 57.5 ounces. Thirty men out of three hundred and seventy-five examined in the West Riding Asylum gave brain weights of 55 ounces and upward, showing that such weights are not so rare as some have supposed. In another asylum in England one out of every dozen brains examined showed a weight of 55 ounces or more.
In Nachrichten, of Göttingen, 1860, pp. 70-71, Dr. Rudolph Wagner gave a table of thirty-two persons whose brains he examined, among whom were five distinguished men; but the largest brain weight recorded in it, 55.9 ounces, has opposite to it the legend, "Idiotic grown man."
To this list we might have added a large number of persons whose brains weighed less than 53 ounces. Yet the brains of Daniel Webster, Agassiz, Napoleon I, Lord Byron, Baron Dupuytren, General Skoboleff, and other famous men concerning whose large brains much has been said, weighed less than this; and we might have appended hundreds of brain weights of idiots, imbeciles, and other insignificant persons, from 53 ounces down to 49 ounces—probably about the average weight in central Europe. In support of our contention is, further, an observation by Dr. Rudolph Wagner in Nachrichten, February 29, 1860, pp. 71, 72, that "very intelligent men certainly do not differ strikingly in brain weight from less gifted men."
Dr. Clendenning presents in the Croonian Lectures the following entries of brain weights of male subjects of different ages, the tendency of which is to show that the male encephalon loses, after it is grown, more than an ounce every ten years: