DIFFICULTIES CAUSED BY PECUNIARY CIRCUMSTANCES. 219 



reward him proportionally to the scientific services he 

 renders it.' l 



Not only have discoverers not been remunerated for 

 their labours, but their usual means of subsistence have in 

 many cases been diminished in consequence of their occu- 

 pation. John Aubrey stated that he ' heard Harvey say 

 that soon after his book on the circulation of the blood 

 came out, he fell mightily in his practice. It was believed 

 by the vulgar that he was crack-brained. And all the 

 profession were against him. He was also called " the 

 circulator." ' This part of the subject is, however, more 

 fully treated of in Chapter XXVIII. on the ' Circumstances 

 and Occupations favourable to Scientific Eesearch.' 



CHAPTEK XXV. 



COST OF SCIENTIFIC RESEARCHES. 



RESEARCHES differ greatly in expense, but the cost of those 

 in physics and chemistry is not usually great ; for materials 

 and apparatus it does not often exceed a hundred pounds 

 a year. The chief cost consists in the time required ; 

 nearly every scientific discovery of importance, if the 

 time, skill, and money expended upon it were paid for at 

 the same rate as high-class ability in medicine, law, or 

 commerce, would cost at least several thousand pounds. 



Harvey expended nineteen years of labour in order to 

 discover fully the circulation of the blood throughout its 

 entire course. Newton's work also was tremendous. He 

 published his great book, the Principia, in 1687, and at 



1 Conferences ; Special Loan Collection, South Kensington Museum, 

 1876, vol. ii. pp. 83-86. 



