Makch 1, 1898.] 



KNOWLEDGE, 



63 



the sun's mass. But Dr. Gill found a parallax of 0'38", 

 and ])r. See computes from bis own orbit and this 

 parallax that the mass of the system is 3'473 times the 

 mass of the sun. ■ Now I lind that if the sun were placed 

 at the distance indicated by Dr. Ci ill's parallax it would be 

 reduced to a star of I'tiT magnitude, or 3-10 magnitudes 

 fainter than Sirius. This implies that Sirius is 17'38 

 times brighter than the sim would be at the same distance. 

 But if Sirius were of the same density and intrinsic 

 brightness as the sun, its mass would imply that it should 

 be only 1-773 (2-3G)' ■ brighter than the sun. Hence 

 we see that Sirius is nearly ten times brighter than 

 it would be had it the same density and brightness of 

 surface as the sun has. Hence, as Dr. See says, "there 

 is some reason to suppose that sirius is very much 

 expanded, more nearly resembling a nebula than the sun." 

 i{> Ursse Majoris is a very brilliant star. Here we have 

 the sun reduced to a star of 8'55 magnitude, or a 

 difference of i-V2 magnitudes in favour of the star. Hence 

 B=-14-47 and h = .,.\j. The spectrum is of the Sirian 

 type. For y Cor.'JBor., I find B = 8-091 and n = ..\^. 

 y Centauri is another brilliant star. Here B = 29-38 and 



There are two remarkable cases in which the sun, if 

 placed at the distance indicated by the " hypothetical 

 parallax," would be considerably hriijhtir than the binary 

 star. One of these, |x' Herculis, is referred to in a former 

 paper (Knowledge, December, 1894). Here, the sun 

 would be reduced to 1-36 magnitude, and, taking the star's 

 magnitude as 9-4, we have a difference of about five 

 magnitudes in favour of the mn. This would nduce the 

 star's parallax to 0011', and would make its mass no less 

 than one thousand times the mass of the sun ! The star 

 being so faint its spectrum has not been determined, but 

 it forms a distant companion to ix.- Herculis, the magnitude 

 of which was measured 3-49 at Harvard, or nearly one 

 magnitude brighter than the sun would be if placed at the 

 " hypothetical " distance. If we increase its distance ten 

 times, as indicated by the above calculation, we must 

 conclude that ju.- Herculis is no less than two hundred 

 and twenty-three times the brightness of the sun ! 

 According to the Draper Catalogue the brighter star has a 

 doubtful spectrum of the solar type (Class II. :'). As both 

 stars have a common proper motion, they probably lie at 

 practically the same distance from the earth, and the only 

 explanation of the above startling results seems to be that 

 the binary star has — like the companion to Sirius — cooled 

 down, and is, therefore, not comparable in its physical 

 constitution with the sim. 



Another remarkable case is that of p 883— a binary of 

 very short period, whose rapidity of motion has recently 

 been discovered by Dr. See. Here the difl'erence of bright- 

 ness is about four magnitudes in favour of the sun, which 

 would make the mass of the system about two hundred 

 and fifty-one times the sun's mass ! But here again we do 

 not know the character of its spectrum, so cannot say 

 whether the star is really comparable with the sun in 

 brightness. 



.^ 



^YE understand that Mr. Thomas H. Blakesley, m.a., c.e., 

 the weU-knowD instructor in physics and mathematics at 

 the Royal ^aval College, Greenwich, has resigned his seat 

 at the Coimcil Board of the Physical Society of London. 

 Mr. Blakesley is, therefore, no longer Honorary Secretary 

 of that learned body. 



* The mass of the bright star is 2 36 times the mass of the 

 sun. The mass of the companion, which is very faint (and does not 

 aifect the brightness of the primary), is, according to Dr. See, 1-113 

 times the sun's mass. 



H.R.H. the Prince of Wales has graciously consented 

 to open the International Photographic Exhibition at 

 the Crystal Palace. Intending exhibitors are asked to 

 note that the date of opening of the Exhibition by His 

 Royal Highness has been fixed by him for Monday, 

 April 25th, and not Wednesday, April 27th, as originally 

 announced. The latest date for the reception of exhibits 

 in each section will therefore be two days earlier than 

 that first stated on the prospectus. 



The number of applications for patents during the year 

 1897 was thirty thousand nine hundred and thirty-six, as 

 compared with thirty thousand one hundred and ninety-four 

 in 1896 and twenty-five thousand and sixty-five in 1895. 

 Although the number of patents applied for illustrates the 

 progress of inventive activity, it does not atfjrd any reliable 

 criterion as to the number which arrive at maturity. Out 

 of the thirty thousand one hundred and ninety-four in 

 1896, for example, only thirteen thousand three hundred 

 and sixty were completed, the rest being allowed to lapse 

 after the nine months' protection. Not a few of the 

 applicants for patents are women, of whom there were 

 about seven hundred in 1896 ; some hundred and fifty of 

 these inventions relating to dress. 



A new bibliography of great value to scientists is now 

 being prepared of ah the technical works in that unique 

 and most easily accessible collection, the Patent Oflice 

 Library, and will be completed in two volumes. In the 

 first volume the books and pamphlets, etc., will be indexed 

 under the names of authors, and the second volume wiU 

 be a subject-matter index. A proof, including the letters 

 .\, B, C, D, consisting of two hundred and forty pages of 

 the first volume, has been placed in the Library for the use 

 of the public. 



Notitfs of Boolts. 



Tlw New Psychology. By Dr. E. W. Scripture. Illus- 

 trated. (Walter Scott.) 63. By such a book as this, 

 belonging to the Contemporary Science Series, psychology is 

 lifted out of the arena of abstract philosophy and established 

 upon the sound basis of experimental science. The develop- 

 ment of the new or experimental psychology within the 

 last few years has produced a large amount of remarkable 

 material which has remained almost unknown except to 

 speciahsts. Most of this work has been done in Germany 

 and the United States, and Dr. Scripture is one of the 

 foremost of the workers. What a vast amount of material 

 has been accumulated may be seen by reference to the 

 " Psychological Index," or those two excellent journals the 

 Psychdoijicid Review and the Journal of Psychology — the 

 like of which do not exist in this covmtry. Perhaps, now 

 that a psychological department has been established 

 at University College, we may also be able to give similar 

 hostages to fortune. The fact is that many men of science 

 in this country are disinclined to give psychology a locus 

 standi : the chemist and physicist look upon it as akin to 

 metaphysics, and the physiologist regards it as a pre- 

 sumptuous sub-department of his branch of natural 

 knowledge. It is not clear why physiologists generally do 

 not look with eyes of favour upon this younger science, for 

 surely it is immaterial what designation is given to any 

 department of scientific work so long as facts are being 

 accumulated. Moreover, the barriers between the various 

 sciences are being broken down daily. The methods and 



