252 



NATURE 



[November 4, 19 15 



standing facts of natural knowledge is overlooked. 

 A well-known writer has unkindly said, "The 

 man of science appears to be the only man in the 

 world who has something to say, and he is the 

 only man who does not know how to say it." The 

 retort invited by this remark is that the man of 

 letters frequently has nothing to say, and he says 

 it at great length. The first business of the man 

 of science is to create new knowledge, and not 

 necessarily to clothe his discoveries in a pleasing 

 dress, though he may do so. The facts of science 

 provide material upon which literary art may be 

 exercised, but the two functions of exploration and 

 fine expression are rarely found together. 



The methods of accurate observation and cautious 

 interpretation demanded of scientific investiga- 

 tors do not readily lend themselves to attractive 

 description, and the results require more mental 

 concentration to understand them than is usually 

 demanded of a literary performance. A writer 

 of romance can let his imagination have free play, 

 but when natural occurrences enter into the story 

 they should be presented accurately if the material 

 is to be used rightly. Nothing is easier than to 

 be deceived by appearances, or to accept an asser- 

 tion without inquiring into its foundations. The 

 scientific plan of asking for evidence, and of limit- 

 ing statements to those for which good justifica- 

 tion can be produced, is much more tiresome, yet 

 it is the only way by which truth can be attained; 

 and that, after all, is the highest aim. 



Writers in the popular Press, and in technical 

 papers also, frequently indulge in cheap sneers at 

 what they call "scientific theory." In their minds 

 the man of science lives in a world far removed 

 from the realities of life, and knows Httle of material 

 things or practical possibilities. Nothing could 

 be more incorrect than this view. With the ex- 

 ception of pure mathematics and metaphysics, 

 every branch of physical and natural science 

 depends for its progress upon practical work in 

 the laboratory or the field. No one appreciates 

 the value of experimental work more than the 

 man of science, and no one is more critical of 

 scientific theory. Whenever a theory is put for- 

 ward in scientific circles, it is always subjected to 

 severe attack from people most competent to point 

 out its weaknesses; and, in any case, it only sur- 

 vives until someone brings forward evidence which 

 disproves it. 



Whether the world recognises it or no, all its 

 material advance has been achieved by men of 

 science. In the arts of sculpture and architecture, 

 in literature, in philosophy, the position gained by 

 Greece two thousand years ago remains the 

 NO. 2401, VOL. 96] 



standard of excellence for the moderns, whereas 

 the last fifty years or so have seen more additions 

 to natural knowledge than all the ages before 

 them; and the result has been not only advance 

 in material welfare and comfort, but also in intel- 

 lectual outlook. The present era will not be 

 •remembered in future history for its art, its litera- 

 ture, or its drama, but for its science, by which 

 it is placed pre-eminent above all others. Though 

 this is undoubtedly the case, the public is still 

 guided and taught chiefly by men who know little 

 or nothing of scientific methods or modern learn- 

 ing. It is not surprising that under these condi- 

 tions the nation has yet to learn how to derive 

 the highest advantage from the great scientific 

 forces at its disposal. 



THE CQMPLETE WORKS OF TYCHO 



BRAHE. 

 Tychonis Brake Opera Omnia. Tomus II. Edidit 



I. L. E. Dreyer. Pp. 461. (Copenhagen : 



Nielsen and Lydiche, 1915.) 



THE first volume of this sumptuous reprint 

 of the complete works of Tycho Brahe was 

 noticed in Nature last April. . There will be thir- 

 teen volumes in all, of which the second has now 

 appeared, containing the first and second of the 

 three parts of the Progymnasmata. This is a 

 posthumous work, as although a large portion of 

 it was printed at Hveen under Tycho 's direction, 

 it was not completed until 1602, the year after his 

 death ; Kepler saw it through the press, and added 

 an appendix. It is a general treatise on astro- 

 nomy, both observational and theoretical ; it com- 

 mences with a dedication to the Emperor Rudolph 

 II., and the diploma that he granted to Tycho. 

 A document follows that is of special interest to 

 British readers; it is the "privilege" of copy- 

 right in Scotland for thitty years, granted to 

 Tycho by James VI. on the occasion of his visit 

 to Hveen in 1590, just after his marriage to Anne 

 of Denmark. Two Latin epigrams that were sent 

 to Tycho by James are also printed. 



The motion of the sun is the first astronomical 

 problem discussed. Tycho in the beginning 

 followed his predecessors in assuming that the 

 solar orbit round the earth is an eccentric circle, 

 described with uniform motion. This assumption 

 involves adopting an eccentricity of the orbit that 

 is just twice the true value. Shortly before the 

 close of his life, he and Kepler detected the error 

 of this assumption; it was too late to alter the 

 matter in the text, as the sheets had been struck 

 off, but Kepler drew attention to this correction, 

 and some similar ones, in the appendix which he 

 added. 



