Jan. 27, 1882.] 



• KNOV/LEDGE - 



265 



found in the London and Edinburgh Philosophical Maga- 

 ziw, July, 1800, the same facts under the guise of mathe- 

 matical deductions, with so meagre a- reference to what 

 Draper had done, that he secured the entire credit of these 

 discoveries. In an liistorical sketch of spectr\im analysi.';, 

 subsequently published, Kirehhofl' avoided all mention of 

 his American predecessor. 



"Dr. Draper was the first person who succeeded in taking 

 portraits of the liuman face hy photography. This was in 

 1839. He published a minute account of the process at a 

 time when in Europe it was regarded as altogether imprac- 

 ticable. He also was the first to take photographs of the 

 moon, and presented specimens of them to the New^ York 

 Lyceum of Natural History, in 1840. 



" A Treatise on Human Physiology, Statical and Dyna- 

 mical,' became a standard textbook in American colleges. 

 It has passed through a great many editions, and was 

 translated into several foreign languages. The Russian 

 edition is used in the higher schools of that country. A 

 yet more important work is his 'A History of the Intel- 

 lectual Development of Europe,' thus described in the 

 Westminster Review: — 'It is one of the not least remark- 

 able achievements in the progress of positive philosophy 

 that have yet been made in the English tongue : a noble 

 and even magnificent attempt to frame an induction from 

 all the recorded phenomena of European, Asiatic, and 

 North- African history.' " [Of this treatise, Dr. Draper's 

 later work, "The Conflict of Science and Religion," may be 

 regarded as in some sense an abstract. It is severe in its 

 treatment of religious intolerance and dogmatism, and does 

 not seem to do full justice to the motives which in many 

 cases have actuated religious persecutions. But the book 

 is the product of a healthy and vigorous mind, and, setting 

 aside the undue hardness of its tone in certain places, it 

 must be regarded as a work which has done, and is calcu- 

 lated to do, an immense deal of good.] 



" Though in his earlier years Dr. Draper was a skilful 

 mathematical analyst, he has published but few niathe- 

 matical papers, the most impoi-tant being an investigation 

 of the electrical conducting power of wires. This was un- 

 dertaken at the request of Prof. Morse, at the time he was 

 inventing his telegraph. The use made by Morse of this 

 investigation is related by him in ' Silliman's American 

 Journal of Science and Arts,' December, 1843. The 

 paper shows that au electrical current may be trans- 

 mitted tlirough a wire, no matter what the length may be, 

 and that, generally, the conducting effect of wires may be 

 represented by a logarithmic curve. Among electrical 

 memoirs there is one on the tidal motions exhibited by 

 liquid conductors, and one on the electro-motive power of 

 heat, explaining the construction of some new and im- 

 proved forms of thermo-electric batteries. An abstract of 

 these improvements is given in the last edition of the 

 ' Encyclopjedia Britannica ' (Art. Voltaic Electricity). 



" Dr. Draper was the first person to obtain photographs 

 of the diffraction spectrum given by a grating, and to show 

 the singular advantages which that spectrum possesses 

 over the prismatic investigations on radiations. In a 

 memoir on the production of light by chemical action 

 (1848), he gave the spectrum analyses of many different 

 flames, and devised the arrangement of charts of their 

 fixed lines in the manner now universally adopted. A 

 memoir on phosphorescence contains the experimental 

 determination of many important facts in relation to that 

 property. Among purely chemical topics he has furnished 

 a method for the qualitative determination of urea by 

 nitrous acid." 



[From 1860 to 1870 Dr. Draper did but little in scientific 

 research, devoting himself mostly to historical works. 



During this time lie published his " History of the 

 American Civil War," in three volumes.] 



" In the summer of 1870, Dr. Draper sufi'ered a severe 

 bereavement in the loss of his wife. Of Brazilian birth, 

 she was connected with an ancient and nobh' Portuguese 

 family. She had rendered his domestic life a course of 

 unbroken happiness, and doubtless she was the exemplar 

 before his eyes when h(^ wrote that oft-quote<l passage in 

 his Physiology,' in which, after depicting the physical 

 and intellectual peculiarities of woman, he says : ' I5ut it 

 is in the family and social relations that Jier beautiful 

 qualities shine forth. At the close of a long life, checkered 

 with pleasures and misfortunes, how often does the aged 

 man with emotion confess that, though all the ephemeral 

 accjuaintances and attachments of his career have ended in 

 disappointment and alienation, the wife of his youth is still 

 his friend '! In a world from which everything else seems 

 to be passing away, her affection alone is unchanged ; true 

 to him in sickness as in health, in adversity as in pro- 

 sperity, true to the hour of death.' " 



Of their six children, one died in infancy ; the survivois 

 are three sons and two daughters. Of the former, the 

 eldest. Dr. Henry Draper, Professor of Natural History 

 in the College of the City of New York, is eminent as a 

 physicist and astronomer; the second, Dr. John C Draper, 

 is Professor of Physiology in the University of New York ; 

 the third. Dr. Daniel Draper, is Director of the Meteoro- 

 logical Observatoiy in the New York Central Park, where 

 he has exercised an important influence in de\elopiiig 

 the meteorological system of the United States. In 

 recent years. Dr. Draper has published two short memoirs : 

 one, on the " Distribution of Heat in the Spectrum," 

 showing that the predominance of heat in the less re- 

 frangible regions is due to the action of the prism, and 

 would not be observed in a normal specti'um, such as is 

 formed by a grating ; and that all the rays of light have 

 intrinsically equal heating power ; the second an in- 

 vestigation of the distribution of chemical force in the 

 spectrum. The Popular Science Monthly notes to his 

 credit that " these scientific researches, to wliich so many 

 years of his life have been devoted, liave been at his own 

 expense ; he has ni^er received any extrancoua aid, though 

 many of them have been very costly ; he has rxcer taken out 

 any patent, but has given the fruits of his investigations 

 and inventions freely to the jniblic." 



THE GREAT PYRAMID. 



By the Editor. 



IN No. 10 we showed how the buildeis of the Great 

 Pyramid, in carrying out what obviously was their 

 purpose, the exact orientation of the building, would have 

 been led to construct those passages, descending and 

 ascending, which actually exist in the building, with pre- 

 cisely the slopes we should expect to find ; but we did not 

 pass beyond the smaller of the ascending passages ; and, 

 indeed, it is to be noticed that in passing upwards froiri 

 the upper end of this passage we recognise another 

 plan. All the features thus far liavc been such 

 as we should expect to find in a ma-ssive structure 

 such as this, intended — for whatever leason — to be 

 very carefuUy oriented. Tliey are such, in fact, 

 as could not but exist in a building oiiented so 

 successfully as the Great Pyramid unquestionably is, unless 

 some utterly incredible chance had enabled the builders, by 

 an imperfect method, to hit accidentally on so perfect an 

 orientation. Even then, in passing from tlie ground level 



