Classification of the races
In the mid-eighteenth century, Carl von Linné, the great Swedish naturalist, put graphic order into the hidden order of nature. In the first edition (1735) of his Systema Naturae, he divided the natural world into three kingdoms: mineral, plant, and animal. He introduced what became the standard nomenclature by which to identify plants and animals – that is, the taxonomic categories of class, order, genus, species, and variety. He placed humans in the class of Quadrupedia, the order of Anthropomorpha (also including simians ‒ apes and monkeys ‒ and sloths), and in the genus Homo, with four species: H. Europaeus (white), H. Americanus (red), H. Asiaticus (dark), and H. Africanus (black) (Linnaeus 1740, 44). By the highly revised tenth edition of his work (1758‒1759), Linnaeus mark- edly changed his classification scheme. He replaced the class name Quadrupedia with Mammalia and changed Anthropomorpha to Primates. He divided the order of primates into four genera: Homo, Simia, Lemur, and Vespertilio (bats). The genus Homo now had two species, H. sapiens and H. troglodytes (caveman or, as he was also termed, “man of the night”) ‒ the latter included the subspecies Orang
Outang and Kakurlacko (perhaps a gibbon). The species H. sapiens had six varie- ties: H. Americanus, H. Europaeus, H. Asiaticus, H. Africanus, H. Ferus (wild man ‒ chimpanzee?), and H. Monstrosus (macrocephalics, etc.). The first four human racial varieties, the ones that survived Linnaeus’s classification scheme, carried several descriptors, including a too-neat application of the four Hippo- cratic temperaments: the Americans were red, choleric, straight-standing, and governed by custom; the Europeans were white, sanguine, muscular, and gov- erned by law; the Asians were dark, melancholic, stiff, and governed by opinion; and the Africans were black, phlegmatic, languid, and governed by caprice (Lin- naeus 1758‒1759, I, 20‒24).
Blumenbach, in his doctoral dissertation ‒ De generis humani varietate nativa (1775; On the Natural Variety of Humankind) ‒ initially adopted the fourfold divi- sion of the human races established by Linnaeus (Blumenbach 1775, 41‒42), and he insisted upon a basic principle: the unity of humankind (Blumenbach 1775, 40‒41). Using Georges-Louis Leclerc de Buffon’s criterion of hybrid fertility as an indicator of membership in a particular species, Blumenbach represented humans as forming four varieties of a single species. He also constructed their geographical boundaries somewhat differently from Linnaeus ‒ for instance, he included among the European group individuals living just west of the Ganges River (thus including Indians and, further north, the Caucasians); the Mongo- lian group he made to include Native Americans living in the northwest areas of the American continent. He later added, in his Handbuch der Naturgeschichte (1779‒1780; Handbook of natural history), one more variety or race: the south Asian and Polynesian (later called the Malay). During the late eighteenth and early nineteenth centuries, Blumenbach’s fivefold division of the races became standard.
All men, according to Blumenbach, descended from Adam and Eve, and thus formed a unity; but because of environmental forces, they developed into five varieties or races. The closest to the original progeny were the Caucasians, whom he named after the Caucasus Mountains, today on the border of Georgia and Russia. They were “the original and greatest race,” of white skin color, which must have been the original color of men. He supposed that the skin color of the original group had been white since it would be easier to transition from white to other skin colors than the reverse (Blumenbach 1795, 303). In appearance, the Caucasians were “according to our judgment of symmetry, the most beautiful and the best formed of men” (Blumenbach 1795, 289). The other races showed domi- nant characteristics: the Asiatics, with yellow-brown coloring, flat face, and small eyes; the Africans, of black color, wooly hair, squat nose, and full lips; the Americans, of copper-red color; and the South Asians and Polynesians (i.e., the Indone- sians and Filipinos) with dark hair and light brown skin (Blumenbach 1779‒1780, I, 63‒64). The differences among men, according to Blumenbach, shaded into one another, so that the pale white skin at one end of the spectrum in the German population transitioned to the red skin of the Americans at the other end, and so through the other populations; the same gradations could be found in stature and other features. The various groups displayed predominant traits by reason of particular environmental forces but expressed features just as variegated as the distinctive nutrition and climate of those environments and the diverging customs of the peoples. He thought Linnaeus’s monstrous men (e.g., albinos) were mostly men suffering from some disease, and the troglodytes were confections of tales about matings of men and orangutans (Blumenbach 1779, I, 63‒64).
In the first edition (1775) of his treatise De generis humani varietate nativa, Blumenbach, following Buffon, assumed that climate, nutrition, and habit had altered originally created stocks of animals and men, producing the varieties of species then populating the earth. But in the second edition of his treatise (1781b, 1‒2), he introduced an additional, explanatory factor, the Bildungstrieb (forma- tive drive). This was an independent vital agency, which he postulated initially to explain the epigenetic formation of the fetus, as opposed to the supposition that the fetus was already preformed, a kind of miniature adult that had only to unroll (evolvere) (Blumenbach 1781a). This force also accounted for the regular growth, maintenance, and repair of the individual, functions that could not be given a simple, mechanistic interpretation. He regarded this power as comparable to Newton’s gravitational force ‒ a power postulated to explain phenomena, even though the ultimate cause remained obscure. Blumenbach thought the Bildungstrieb could thus explain general species structures, but additionally supposed that it could be deflected from its regular operations by different climates, diets, and habits; the force, in concert with the environment, should thus be regarded as “the mother of varieties properly so called” (Blumenbach 1795, 88). The concept of the Bildungstrieb became a staple in German biology at the end of the eighteenth century, being adopted by the likes of Johann Wolfgang von Goethe, Johann Got- tfried Herder, Alexander von Humboldt, and even Kant (Richards 2002, 216‒37).
Through the latter part of the eighteenth century, the classification of the races and the nature of racial traits grew in moral urgency along with the escalation of the slave trade. In Britain and the new American nation, various abolition move- ments brought the moral question constantly before the public.
The quantitative analysis of skulls
Tiedemann and slavery
The German lands were not engaged in the slave trade, and many prominent Ger- mans (e.g., Alexander von Humboldt, Friedrich Blumenbach, and Georg Forster) expressed indignation at its evils. Friedrich Tiedemann (Figure 9.2), a liberally inclined anatomy professor at Heidelberg, deployed not a philosophical argument against slavery but a scientific argument: he measured skulls.
Tiedemann was born in 1781 into a professorial family; his father, Dietrich Tiedemann, was a professor of philosophy in Cassel and an opponent of Kant. At the time, Cassel had a small Negro population, some arriving in the mid-seventeenth century and others a century later from the United States, families of individuals who had fought with the Hessian allies of the British during the American Revolutionary War (Jones 2013). Tiedemann would quite likely have been acquainted with individuals of this group. He studied medicine at Bamberg, Würzburg, and Marburg, receiving his degree from the latter in 1804. During a three-year itinerant period, he came to study with Blumenbach at Göttingen, the philosopher Friedrich Wilhelm Joseph Schelling at Würzburg, and the zoologist Georges Cuvier at Paris. Along the way, he heard lectures from Franz Joseph Gall, who argued for a close connection between configurations of the skull and mental traits ‒ the foundations for his doctrine of phrenology. The anatomist Samuel Thomas Soemmerring recommended this extraordinarily talented naturalist for a position at Landshut (in southeast Bavaria), where he stayed for ten years, focus- ing his attention on comparative anatomy. In 1816, he received a call from Hei- delberg, where he happily spent the rest of his professional life, some thirty-three years.
While at Landshut, Tiedemann conducted studies of brain development, using two approaches that allowed him to move beyond description to explanation: comparative anatomy, on the one hand, and studies of the development of the human fetal brain on the other. He regarded this latter as “the thread of Ariadne for this Labyrinth” (Tiedemann 1816, 2). Following that thread led him to a cau- tious statement of a natural law of human development: the human fetal brain in its growth recapitulates the stages of brain structures represented by the series of animals from lowest to highest (Tiedemann 1816, 148). So, for example, though the thickness of the spinal cord in relation to the cerebrum of the human adult is quite small relative to that of other animals, in the early fetus it is relatively large but gradually diminishes in size comparable to the narrowing of the cord when one passes from fish, to amphibians, to birds, and finally to mammals (Tiedemann 1816, 91‒92). Tiedemann likely would have been familiar with recapitulation theory at Würzburg, especially in his interactions with Schelling and the natural- ist Lorenz Oken.2 Tiedemann’s own attachment to this conception directed him to that “daring adventure of reason” of which Kant spoke – namely, an evolutionary hypothesis about the origins of life on earth.3 The developmental and comparative focus of German zoologists like Tiedemann in the early nineteenth century made the acceptance of Darwin’s theory later in the century much smoother than in other European countries, including England.
Tiedemann insisted that human physiology was an experiential science (Erfahrungs-Wissenschaft), a science in which one gathered facts through system- atic observation and performed experiments to discover their causes. “In observa- tion we listen to nature, as it were; in experimentation we ask nature for advice.” The attentive ear was important since many false moves arose from being in thrall to a “favorite theory” (Lieblings-Theorie). Any speculations had to be tested by experience (Tiedemann 1830, I, 9‒11). Tiedemann brought this exacting experi- mental attitude to the study of human skulls. He wished to test whether there were significant differences among the races that might indicate differences in intellect, talent, and moral capacity. His first publication on the comparative anatomy of skulls came, quite surprisingly, in English: a paper read before the Royal Society of London, “On the Brain of the Negro,” and printed in the Transactions of the Society in 1836 (Tiedemann 1836). The paper had been originally sent to the journal in 1835. Shortly thereafter, in 1837, he published a small book in German on the same subject but with a larger set of data and an extended analysis (Tiedemann 1837).
Pertinent and enduring conclusions came forth from Tiedemann’s extensive study ‒ ultimately of some 430 skulls (Figure 9.3). Among those conclusions were: the brain, relative to body size, is largest during infancy and reaches its mature size in humans at about the seventh to the eighth years of age (we would now say tenth to twelfth years); brain size is generally proportional to body size, though with great variation; females, having smaller bodies, tend to have slightly smaller brains than males ‒ though in relation to body size, slightly larger brains. Tiedemann dissented vigorously from the racial evaluations of Peter Camper, Cuvier, and especially Soemmerring, each of whom held that the Negro brain was more like that of the orangutan than that of the European. Tiedemann found no morphological differences between the Negro brains and the European brains that he dissected. Brain size, however, was less easy to determine and might be different. Size was the crucial factor since there was, as he thought, “a very close connexion between the absolute size of the brain and the intellectual pow- ers and functions of the mind” (Tiedemann 1836, 502). Soemmerring placed the African skull at the diminished end of the series running from the European to the Asiatic to the African (Sömmerring 1785, 19). His study, though, was quite circumscribed. His investigations of the Negro body relied on one female and a couple of males that he dissected at Cassel. Tiedemann’s sample was vastly larger and the measurements more than eyeballing. His conclusion: “our investigation demonstrates undeniably that those anatomists and naturalists have been caught in error who have attributed to the Negro a cranial cavity of less volume and a smaller brain than the Europeans and the peoples of other human races” (Tiedemann 1837, 47).
Tiedemann used a fairly simple method of determining cranial capacity. He first weighed skulls of different races and genders, as well as the skulls of apes; he then filled the cranial cavities with millet seed and weighed the skulls again. By subtracting the results, he got the size of brains as weighed in millet seeds. He found that most of the individual skulls of each of the five races ‒ Ethiopian, Cau- casian, Mongolian, American, and Malay ‒ could be found in a range of 42‒32 troy ounces. He also noted the number of skulls that exceeded 42 ounces (see Fig- ure 9.3). Tiedemann concluded rather carefully, “The cranial cavity and the brain of all the human races show a similar middling size, within certain fluctuating lim- its.” Thus, the majority of the sampled individuals of each race lay within the 42- to 32-ounce range. The next sentence, however, seemingly qualifies his results: “The most that can be shown is that among the peoples of the Caucasian and Malay races, according to the facts I’ve laid out, some men more often achieve a considerable size than with the peoples of the other races” (Tiedemann 1837, 47). His phrase “most that can be shown” is borne out by the figures: 5/70ths of the Negro skulls (about 7%) but 42/186ths of the Caucasian skulls (about 23%) and 21/98ths of the Malay skulls (about 21%) were over 42 ounces.
Carus, who believed there were permanent differences separating the races, critically noticed that Tiedemann’s own figures showed that the number of Negro skulls in the sample that exceeded 40 ounces amounted to 6 of 54, or about 11%, while the number of Caucasian skulls over 40 ounces was 64 of 141, or about 45% (Carus 1841, 12). Read that way, the portion of big-skulled Caucasians stands out, a jutting conclusion of which Tiedemann seems to have been aware. In antici- pation, Tiedemann provided some mitigating considerations. He suggested, for instance, that the bodies of Negros were generally of smaller stature than those of Caucasians; thus, relative to body size the two groups of skulls simply did not differ that much ‒ though Tiedemann admitted to not having exact figures. He also observed that slaves, whose skulls generally constituted the bulk of the Negro numbers, were usually taken from coastal areas of Africa, where the blacks lived a more degraded life than in the highlands. He also mentioned the case studies made by his old teacher Blumenbach of Negros who had achieved considerable intellectual renown in theology, philosophy, poetry, and science.
Samuel George Morton, the American measurements
The best-known quantitative effort to scale race in the nineteenth century is that of Samuel George Morton (Figure 9.4), a Philadelphia physician and naturalist. During his own time, numerous researchers ‒ Louis Agassiz, Paul Broca, and Carl Gustav Carus ‒ as well as Southern slave owners admired his work and used his skull measurements as evidence of racial hierarchy. Even Alexander von Humboldt, no friend of slavery, sent a letter of congratulations upon receipt of Morton’s principal study of skulls, Crania Americana (1839); the German adven- turer prized the “profundity of its anatomical views” rendered without “poetical reveries.”5 In our time, Stephen Jay Gould (1996, 82‒101) found more poetry than science infusing Morton’s craniology; he reanalyzed the measures and methods, judging them tainted by prejudicial assumption and poor technique. Then again, these very charges have recently been redirected at Gould himself.
Morton was born at Philadelphia in 1799 of Irish descent and Quaker upbringing. While taking private lessons in medicine, he attended lectures in anatomy and physiology at the University of Pennsylvania, from which he received an MD in spring of 1820. He undertook further medical training at Edinburgh beginning later that year, arriving in the city a few years before the young Charles Darwin began his own medical studies (1825). The next year he went on to Paris, lingering long enough to let slip away his Quaker observance and to suffer the enticements of the bright, flickering lights. He made his way to northern Italy and then in fall 1822 back to Edinburgh, fulfilling the requirements for a diploma in medicine in August 1823. He returned to Philadelphia in June 1824, where he punctuated a desultory medical practice with the stimulus of research, initially in pathology. He also quickened a recumbent interest in geology, paleontology, and compara- tive anatomy, all of which he had pursued as a member of the Philadelphia Academy of Natural Sciences, initially becoming a member just after receiving his MD. He worked his way up the administrative ladder of the Academy, eventually becoming its president in 1849. He was appointed professor of anatomy in 1839 at the Pennsylvania College of Medicine, the same year he saw published his extraordinary quantitative study of American Indian skulls, his Crania Americana (Figure 9.5).
For Crania Americana, Morton not only measured the skulls taken from various Indian tribes but also compared them with skulls of other races, those groups discriminated by Blumenbach. The study also included considerable ethnographic materials culled from reports of travelers, missionaries, and naturalists. Morton’s fame rests principally on this book, replete as it is with precise measurements of some 253 skulls and dramatic lithographs of those immortal parts. He supplemented this study with two other compendia of skull measurements, his Crania Aegyptiaca (1844), for which he measured the skulls of Egyptian mummies, and his Catalogue of Skulls of Man and the Inferior Animals (1849), which corrected some errors of the Crania Americana and both expanded the number of human skulls and added those of animals for comparison.
In Crania Americana, Morton and his assistant calibrated the exterior dimensions (longitudinal diameter, parietal diameter, facial angle, etc.) and internal cranial capacity of adult skulls from the several races, represented by: 144 North and South American Indians, fifty-two Caucasians (Germans, Celts, Semites, South Asians), ten Mongolians (Turks, Chinese, and Tartars), eighteen Malays (Indonesians and Polynesians), and twenty-nine Ethiopians (Africans). He further divided the five races into component “families,” some twenty-two different families in all. Prefacing the report on the actual measurements, Morton provided extensive anthropological descriptions of the races and their constituent families, descriptions collected from travel literature and popular assumption. To measure the skulls, Morton and his assistant used white pepper seed (having a hard and uniform consistency) to fill the cranial cavities of the skulls, and then poured the resulting volume of seed into a standard measuring tube to gauge comparative cranial capacities in cubic inches.
In the later study of 1849, he used lead shot, size BB, instead of seeds, to obtain more reliable measures; and he expanded the number of skulls to 623. The measures in the 1839 study yielded a hierarchy of mean cranial volumes: the Caucasians showing the highest capacity, followed by Mongolians (Asians), Malays, Americans, and Ethiopians (see Table 9.1). The 1849 reevaluation emended the hierarchy, making the African group penultimate and the American group last. These measures, in Morton’s estimation, provided scientific evidence confirming the large number of ethnographic reports he amassed, reports, however, that were often no more than casual observations of travelers. He epitomized his analysis of the races this way: Caucasians have attained “the highest intellectual endowments”; the Mongolians are “ingenious, imitative, and highly susceptible of cultivation”; the Malay are “ingenious, and [possess] all the habits of a migratory, predaceous, and maritime people”; the Americans are “averse to cultivation, and slow in acquiring knowledge, restless, revengeful, and fond of war, and wholly destitute of maritime adventure”; and the Ethiopian are “joyous, flexible, and indolent,” showing diverse intellectual character, of which the “extreme is the lowest grade of humanity” (Morton 1839, 5‒7). These descrip- tions exemplify not so much careful conclusions based on extensive observation as on inertial traditions of description, similar to those easy Hippocratic epitomes made by Linnaeus. Such descriptions usually failed to account for differences in education, a factor Blumenbach made diagnostic of human potential (see ahead).
In Crania Americana, Morton attempted to answer a perplexing question of the time: are the members of the various Indian nations of one species with sev- eral races or do they constitute several different species altogether? He decided that the Native Americans formed one species with two great families, the Toltecans (the “demicivilizations” of Peru and Mexico) and the “Barbarous Tribes” of North America, Brazil, Patagonia, and the tip of South America. This initial question and its answer make sense, however, only if you are of a disposition to regard the various human groups worldwide as specifically different from each other. And Morton was of that disposition, though cautious. He had provisionally adopted Blumenbach’s division of the races, but never explicitly affirmed that all of the races constituted different species. He did conclude, however, that the Americans were specifically different from the other races. Morton, nonetheless, treated Blumenbach’s groups as if they were separate species, even suggesting that their component subgroups ‒ which he called families ‒ had species-like sets of innate features. Their traits were not shaped by the environment after descent from a primordial couple; rather, as he urged, the Creator must have initially rendered each race fit for its specific environment. The purity of these racial lines
could be sullied only by hybridization.
Morton’s argument for the independent origins of the human races precipitated a storm of religious objection from biblical literalists, which he weathered dangling from the elastic threads of Episcopalian theology (Meigs 1851, 34‒36).
Though many prominent naturalists of the period accepted Buffon’s criterion of interbreeding fertility as the marker of species unity, the issue remained in contention. Darwin would later use morphological resemblance as the stand- ard and concluded that the judgment was arbitrary as to whether human beings comprised one species with several varieties or several different species (Darwin 1871, I, 235). Yet in light of the scientific acceptance of Buffon’s standard and the theological heat of the issue, Morton recognized he had to justify his conclusion, which he attempted to do by citing several studies of hybrid fertility in crosses of different animal species and by providing evidence that certain human hybrids had diminished fertility (Morton 1847). So, as he judged, distinct species could hybridize, but not well. He gathered evidence for diminished fertility from incidences of “half-caste” offspring between Caucasians and Native Australians, which by his estimate was very low, about 200 mulattos in a native population of 15,000. However, Morton did not contrast this roughly 1.5% rate against any reasonably expected rate ‒ it just seemed small (Morton 1851). The criterion for species designation he adopted was simply that of consistent morphology over long periods of time: “when races can be proved to possess certain primordial distinctions, which have been transmitted unbroken, they should be regarded as true species” (Morton 1847, 263). The ancient and recent American skulls of his collection, he argued, provided examples of such stable transmission over time. Yet Morton would have required a special vision to perceive, say, the ideal Peruvian skull lying beneath the variability in size, the induced malformations, and the asymmetries of disease and injury, all of which were found in his collection (see Figure 9.6). Herein, I believe, lies a significant difference between Morton and Tiedemann: shining through the variability of individual skulls, Morton perceived the type, while Tiedemann saw only individuals.
Morton thought of his Crania Americana as a treatise in phrenology, and solicited an essay from his friend George Combe, a follower of Franz Joseph Gall, on the general philosophy of phrenology. When Combe wrote the essay, which was appended to Morton’s book, he had only a few of Morton’s plates to consult and none of the measurements. Little matter. Basically, only two general features of the doctrine seemed to concern Morton – namely, that internal psychological dispositions were manifest in external physical structure and that intelligence was proportional to skull size. The Peruvian and Incan skulls did make Morton more cautious about the size-to-intelligence relationship, however. He observed that “it would be natural to suppose that a people [the ancient Peruvians] with heads so small and badly formed would occupy the lowest place in the scale of human intelligence” (Morton 1839, 99). He yet recognized that their architectural accomplishments and the other monuments of a great civilization gave evidence of high intellectual achievement. He thought the same story could be told of the Incas, whose mean skull capacity was 73 cubic inches, lower than that of other peoples, though the remnants of their civilization showed they were superior to most other peoples (Morton 1839, 132). In his review of Crania Americana, Combe, writ- ing anonymously, lauded Morton’s accomplishment but did take issue with the assumption that the ancient Peruvians had small heads but a great civilization. He rather thought Morton might have been misled by skulls that had been artfully shaped, since an important part of the brain might well have been pushed into an area not properly measured (Combe 1839‒1840, 363‒64).
Like Tiedemann, Morton did recognize the great variability of skulls. The largest Incan skull in his collection ran to 89.5 cubic inches and the smallest at 60, with an average of 73. The same scope of variability was evidenced throughout his total collection of over 800 human skulls. Moreover, he knew that the skulls of infants could be molded into different shapes, an art performed by many of the American groups (Figure 9.6). But unlike Tiedemann, he seems not to have recognized the basic principle of allometry ‒ the smaller or bigger the skeleton, the smaller or bigger the skull. For the most part, he had only skulls and not complete skeletons, so judgments of body size were precluded as well as adjustments for size differences between males and females. Of course, distinctions of sex, as well as variability of environment and social status ‒ and what these entail ‒ will alter body size tremendously and thus head size.
Morton prided himself on the meticulous care he took with his skull measurements, and in his Catalogue of Skulls (1849), he corrected many errors that had made their way into Crania Americana. Gould believed Morton’s pride was misplaced. In his Mismeasure of Man (1981; 1996), Gould reanalyzed Morton’s tabulations and discovered what he thought to be unconscious errors that had warped the measures, the calculations, and the conclusions. Morton’s figures, Gould asserted, were “a patchwork of fudging and finagling in the clear inter- est of controlling a priori convictions” (Gould 1996, 86). He discriminated two general kinds of errors ‒ errors of seed measurement and errors of statistical aggregation. Gould assumed that for Caucasian skulls, Morton may have, perhaps unconsciously, packed the seeds into the skulls more tightly, thus giving larger values for cubic capacity ‒ rather unlikely, at least as an error on Morton’s part, since his assistant did the measuring. He also argued that Morton simply took the average of the total number of Peruvian and North American skulls, rather than taking averages of the different tribes and then taking the mean of those averages. (Why this latter method was to be preferred is quite unclear. Gould’s method assumed that each of the tribes was equally represented in the total Native American population, yet neither Gould nor Morton knew what proportion of the whole populations each of the tribes represented.) Gould then corrected Morton’s figures and determined that the five human races differed little from one another in average cranial capacity. Morton himself recognized the measurement errors in Crania Americana, which is why he started using lead shot instead of seeds when he later remeasured skulls in his 1849 study. He also thought he had left too much of the actual work of measurement to a careless assistant, whom he subsequently fired. For the new study of 1849, he did all of the measurements himself and added a much larger sampling of skulls. For instance, he doubled the size of Negro group, bringing the number of their skulls to fifty-eight, and then filled the skulls with lead shot. The new measures elevated the estimate of Negro cranial capacity markedly, from 78 cubic inches to 83 cubic inches for the highest subgroups. Not exactly what one would suspect from a racist finagler, even if this final measure of the highest Negro subgroup stayed below the Caucasian average of 92 for the highest subgroup.
Very quickly after the publication of Morton’s 1849 study, Sir William Hamilton, polymathic naturalist and philosopher, vehemently rebutted Morton’s conclusions concerning racial differences in skull sizes. He observed that Morton did not (and could not) distinguish male from female skulls: “Now, as the female encephalos is, on an average, some four ounces troy less than the male, it is impossible to compare national skulls with national skulls, in respect of their capacity.” (Nor, one might add, could Morton distinguish adolescent from adult skulls.) Hamilton himself, in 1831, had measured skull capacity using sand, and determined that “the Negro encephalos is not less than the European, and greatly larger than the Hindoo, the Ceylonese, and sundry other Asiatic brains.” He specifically mentioned that he agreed with Tiedemann’s conclusion concerning the Negro brain (Hamilton 1850, 330 and 332).
Tiedemann, Morton, and Gould could not provide perfect measures of imperfect objects. They could not control the multitude of factors affecting biological specimens of uncertain provenance. Each trusted in numbers, which the scientific ethos requires. They were less cautious, however, about which numbers to trust. Both Tiedemann and Morton passed their gaze over hundreds of skulls, which varied greatly in size and shape. Morton detected types within the mass of individuals; Tiedemann saw in the proclaimed types only the individuals. These problems of critical judgment and scientific discernment stand highlighted when the standard becomes not quantitative measures of skulls but aesthetic measures of their beauty.