August 26, 1921] 



SCIENCE 



163 



of settlements among neighboring tribes and 

 valuations of tlieir territory as to food sup- 

 ply, allows figures to be set for these other 

 tribes. The figures for the entire district can 

 then be used as a check on estimates made 

 independently from local sources for other 

 districts, due regard being given to variety 

 of geographic conditions. In this way the 

 total is arrived at. 



The best early data are those from Spanish 

 sources, which sometimes include approximate 

 counts. Early American figures are usually 

 impressionistic and exaggerated. 



A check is furnished by the large Tokuts 

 group. Here Moraga in 1806 computed 3,760 

 souls in thirteen tribelets, an average of 290. 

 The inclusion of absentees might bring the 

 figure to 350. Nearly 50 such tribes are known 

 among the Tokuts, with a small part of their 

 area unaccounted for. The total population 

 of the stock thus was about 18,000. Its area 

 embraced about one ninth of modern Cali- 

 fornia and seems about average in food-sup- 

 plying capacity. Multiplying 18,000 by 9 

 gives 162,000. A deduction of one fifth for 

 the larger blocks of high mountain and desert 

 areas brings the total to about 130,000; a 

 reasonable verification. 



Of course, no figure can be more than an 

 approximation; but it seems at least highly 

 probable that the native population fell be- 

 tween 120,000 and 150,000. 



Even this total, the lowest ever arrived at, 

 yields the unusual density of nearly one in- 

 habitant per square mile for aboriginal Cali- 

 fornia. Mooney's estimate is about 1,050,000 

 for the continent north of the Mexican boun- 

 dary; 846,000 within the limits of the United 

 States exclusive of Alaska. 



The latter figure however, seems to contain 

 Merriam's 260,000 for California. Eeduced 

 to conform to the new estimate of 133,000, the 

 population of the United States would not 

 much have exceeded 700,000, or one inhabitant 

 per four square miles. In other words, more 

 than a sixth of the Indians of this country 

 were settled in California. A similarly heavy 

 concentration seems to have held good for the 



Pacific coast of the continent as far north as 

 Alaska. 



The decrease of Indians in California has 

 reached fully 85 per cent, in a century and 

 a half. The factor most favorable to heavy 

 decrease has been immediacy of contact with 

 Caucasians and Caucasian civilization. Other 

 factors have intervened to make the result 

 somewhat irregular; but these are too de- 

 pendent on local circumstances to make their 

 analysis possible here. 



A. L. Khoeber 



TjNrvERsirY of California 



THE CENTENARY OF THE BIRTH OF 

 HERMANN VON HELMHOLTZ 



SoiENTiFio men of the twentieth century 

 are so engrossed in their various pursuits (for 

 which, happily, material equipment far in ex- 

 cess of anything dreamed of fifty years ago 

 is provided) that they are in some danger of 

 forgetting, overlooking or even ignoring the 

 work of their predecessors of the nineteenth 

 century. 



It is upon fundamental discoveries in elec- 

 tricity and magnetism made during that cen- 

 tury, and especially upon the two great gener- 

 alizations, the law of the conservation of energy 

 and the doctrine of evolution, which together 

 constitute its great glory, that the present 

 generation is building a brilliant, though a 

 somewhat complicated and bizarre superstruc- 

 ture. It may be well, therefore, to remind 

 the group of busy younger men who read the 

 pages of Science, that one hundred years ago, 

 August 31, 1821, was born one who must al- 

 ways be ranked with the very first — the three 

 or four very first — of those upon whose work 

 twentieth century science rests. 



Hermann Ludwig Ferdinand, Baron von 

 Helmholtz, was the son of a professor of 

 philology and philosophy at Potsdam. His 

 mother was a Hanoverian lady, a direct de- 

 scendant of William Penn. 



Exhibiting at an early age a fondness for the 

 study of natural phenomena, the necessity for 

 a vocation by which he could earn a living 

 directed him to the medical profession and 

 his first appointment was as an army surgeon. 



