96 REMINISCENCES, ETC. 



contour must be varied in accordance with certain rules to 

 Buit the velocity required. The author then observes, 

 * there is a second point in the wave system which is another 

 element of its general usefulness ; it partakes of the nature 

 of a mathematical maximum or minimum. It is the pecu- 

 liarity of a maximum and a minimum that deviations on 

 either side of it to a moderate extent occasion deviations of 

 magnitude that are comparatively very small. Thus it is 

 that the wave line being considered the curve of least 

 resistance, there are near to it an infinite number of ap- 

 proximate curves which are curves of small resistance, 

 though not of least resistance, and out of them the con- 

 structor is free to choose those which shall best accomplish 

 any other object at the sacrifice of the smallest amount of 

 resistance.' 



" ' To the scientific investigator, it gives precisely that 

 latitude which he desires, to leave him free to work out 

 the intentions of the owners and the uses of the ships he 

 may have to build.' 



" From what has been stated it would appear that the 

 original thought and successful experiments of Thomas 

 Assheton Smith, and the elaborate scientific enquiries and 

 deductions applied by Scott Kussell, stand on grounds widely 

 separated from each other. 



" Believe me to be, dear Sir, 

 " Yours very truly, 



" Roderick I. Murchison. 



" P.S. — Being wholly unskilled in ship-building, I cannot 

 say anything on the hollow lines of Mr. Assheton Smith's 

 vessels, on which he much prided himself" 



This question of the " lines " has occupied a considerable 

 space, but is valuable as illustrating the character of Mr. 

 Smith, and the inflexible firmness of purpose and self- 

 reliance with which he prosecuted his plans. What remains 



