Aug. I, 1872] 



NATURE 



265 



hensive " Pre-Historic Man," which has reached a 

 second edition, he has akeady paid a good deal 

 of attention to the Huron tribe, as well as to other 

 tribes of the North American Indians, which, in fact, 

 constitutes one great feature of value in the work. 



In this \olume Dr. Wilson gave a table of the measure- 

 ments of thirty-seven Huron skulls " obtained from 

 Indian graves to the north of the water-shed bct'.veen 

 Georgian Bay and Lakes Erie and Ontario." The great 

 purpose of the construction of this table, as of so many 

 other investigations made by the author, was to test the 

 truth of a doctrine which had been generally received and 

 was in great measure endorsed by Dr. S. G. Morton, who 

 produced the classical " Crania Americana." This doc- 

 trine, in few words, is that the American race is almost 

 uniform in its head characters from one end of the conti- 

 nent to the other, and that the American typical cranium 

 is distinguished for its shortness. To Dr. D. Wilson's 

 persevering researches we must allow the merit of having 

 shown that there is much variety in native American races, 

 and that in their skulls there is considerable diversity of 

 length. This may be very confidently asserted, without 

 conceding to him an agreement with his assertions respect- 

 ing the long skulls among the ancient Peruvians ; for he 

 evidently mistook the deformed crania of these people for 

 the representatives of the natural form of their heads. 



In the table of the measurements of thirty-seven human 

 skulls referred to, it was seen that their length varied 

 much. If we exclude the " Bavrie skull," No. 23, which 

 appears to be quite aberrantly short, and it is thought 

 has been distorted by art, vm find their longitudinal dia- 

 meter to vary from 7^9 inches to 6 8 inches, or above an 

 inch. The cephalic indices of these two examples, un- 

 fortunately, cannot be accurately calculated from Dr. 

 Wilson's measurements. One of his items of measure- 

 ment is '■ F. D." frontal diameter, which he says in this 

 memoir " is taken from the point of junction of the frontal, 

 parietal, and malar bones." This latter is probably an 

 inadvertence, and should be sphenoidal bone, as the malar 

 bone nowhere joins the frontal. 



Since this table was constructed, thanks to the efforts of 

 Dr. Tache and others, Dr. Wilson has had the oppor- 

 tunity of measuring many more Huron skulls. He now 

 says : '" The sight of upwards of seventy skulls, all derived 

 from the cemeteries of a single tribe or nation, is a pecu- 

 liarly interesting study to the ethnologist. But to one at 

 all impressed with the uniform persistency of a specific 

 ethnical type, the result is far from satisfactory." They 

 are seen to vary materially, and especially in length. The 

 skulls of women present a decided projection of the 

 occiput, and here we may be permitted to allude to Dr. 

 Wilson's plates. The first, which gives shaded profile 

 views of the calvaria of a Huron man and woman, is 

 excellent and very characteristic. Plate II. is lettered, 

 " Long Huron skull, male." It is often very difficult 

 to determine positively the sex in crania, but in this 

 cx.ample it seems doubtful whether the plate does not 

 exhibit the calvarium of a woman. We incline to think 

 that it does. The long oval, vertical view is cjuite appa- 

 rent and unquestionable. Plate 111. is an undoubted 

 instance of a " Long Huron skull, male." 



Dr. Wilson, after attesting the great range of diversities 

 in the Huron skulls he has seen, concludes in these 

 noliceable terms : "But the specialties of the whole, in 

 their front aspect, suggest a greater uniformity in their 

 physiognomy than in cranial conformation. The nose is 

 in most cases large and prominent ; the superciliary 

 ridges in the males are strongly developed ; and a common 

 ethnical character may be traced in the full-face as a whole, 

 including the massive broad cheek-bones and superior 

 maxilla ; as well as in the indications in the greater number 

 of a tendency towards a pointed apex, or meeting of the 

 parietal bones at an angle at the sagittal suture." Perhaps 

 this is as much as anyone can reasonably expect, even 



when divergences are to be acknowledged in the proper 

 calvarial form. And it is difficult to conceive that these 

 divergences are so utter and so puzzling as to prevent our 

 seeing any constancy among them. 



Dr. Wilson, in showing that some tribes of American 

 Indians are characterised by long or dolichocephalic 

 heads, still admits that other tribes have short or brachy- 

 cephalic heads. This must be conceded, as well as that 

 Morton's generalisation was too comprehensive and too 

 literal. Former sweeping conclusions as to dolicho- 

 ceph.aly and brachycephaly cannot now be sustained. It 

 was long since seen that among the crania of any ex- 

 tended race of people, as the ancient Britons, there is 

 much variation as to length, indeed that a scale might 

 be exhibited from the shortest to the longest, in which the 

 num;rou3 intermediate lengths intervene to fill up the 

 ascending degrees of the range. This truth is now more 

 than ever apparent, since the elaborate researches among 

 the skulls of Italian races by the distinguished anatomist, 

 Prof. Luigi Calori, of Bologna. He has conclusively 

 shown that there is much more dolichocephaly among 

 the races of Italy than was previously known. 



Much of the difficulty that craniologists have encountered 

 in the study of the head-forms of different races, has had 

 its foundation in the too rigid rules which they have 

 assumed these forms to observe. Dr. Wilson's labours 

 have served well to illustrate this point in reference to the 

 American races. Were this the proper place, it would be 

 easy to point to examples of the futile labours which have 

 resulted from these self-imposed rules. How many 

 learned controversies have been entertained to determine 

 the race of a man whose only existing relic was his lower 

 jaw.'' On finding that such rules cannot be fixed and 

 defined in so absolute a manner, it has often been the case 

 that other inquirers have lost confidence in craniology 

 itself. This is a transition from one extreme to another, 

 More moderate expectations from the doctrine of skull- 

 forms would have prevented confidence in their value 

 from being so often shaken. Larger views must be taken, 

 but these are quite compatible with our knov/ledge, 

 without any necessary leaning to the meanderings of the 

 evolutionary hypotheses alluded to by our author. 



CONDUCTIVITY OF MERCURY 



IT was shown in a previous article * that solar intensity 

 cannot be accurately ascertained by the thermohelio- 

 meter employed by Pcre Secchi, owing, among other 

 causes, to the imperfect conductivity of the mercury in 

 the bulb exposed to the sun. Meteorologists, however, do 

 not generally accept the assumption that the conducting 

 pov/er of mercury is so imperfect as to affect materially 

 the correctness of the indication of mercurial thermo- 

 meters, Deschanel being quoted in support of the opinion 

 that mercury is not an imperfect conductor. We are re- 

 minded that Prof. Everett, in a recent translation of the 

 works of the author mentioned, assumed that the conduc- 

 tivity of quicksilver in the bulb of a thermometer is the 

 same as a vessel " with thin metallic sides containing 

 water which is stirred" (see Prof. Everett's translation ol 

 " Deschanel's Natural Philosophy," Part II., pp. 245-387). 

 The subject is so intimately connected with the determina- 

 tion of solar temperature and solar energy, that it has be- 

 come indispensable to settle the question by some thorough 

 practical test. Accordingly an apparatus, represented by the 

 following illustration (Fig. i, p. 266) has been constructed 

 by the writer, to ascertain the conductivity of mercury. 

 Before entering on a description, it will be instructive to 

 point out that the heat communicated to the bulb of a 

 thermometer by solar radiation is transmitted to its con- 

 tents chiefly by convection, hence that the altitude of the 

 sun during the observation influences the accuracy of the 

 Natubk, vol. V. pp. 344-3.(7. 



