Mr. Blake's Reply to Mr. Quinbij. 351 



ducting to a method of contemplating mechanical power, 

 which will very much abridge the labour of acquiring defi- 

 nite ideas with regard to it ; if indeed it be not the only medi- 

 um through which such ideas can be attained. This method 

 of considering the subject, opens a door of immediate access 

 to many arcana of the science, at which our predecessors 

 have arrived, by a far more tedious and intricate path ; and 

 developes others, in the pursuit of which they have all been 

 led astray. 



The part of my communication to which Mr. Quinby's 

 question refers, is as follows, viz :— - 



" A certain power will exert a pressure often pounds." 



" Another will drive a body against a given resistance ten 

 feet." 



" Another will elevate water one foot, at the rate of one 

 gallon per minute." 



" The powers necessary to produce these several effects 

 are definite, and may be definitely measured, by referring 

 them respectively to their proper standards. But even after 

 this is done, no one can say that either of them is equal to, 

 or by how much it is greater or less than another, because 

 they are dissimilar in their nature. The first consists of one 

 attribute only, like linear measure. The second, of two, like 

 superficial measure. The third, of three, like solid measure. 

 To say, therefore, that one of them is greater or less than 

 another, would be as absurd as to say that a mile is greater 

 than a square foot, or that a square foot is less than a cubic 

 inch." 



Mr. Quinby's reference to this, and question, are as fol- 

 lows : — 



" At page 339, he [Mr. Blake] says, ' another [power] will 

 drive a body against a resistance* ten feet ;' this, he states, 

 contains but two attributes ; but can a body move ten feet 

 without occupying some portion of time ? and if it occupy 

 any portion of time, does not this example contain the three 

 attributes ? How then does Mr. Blake find the same differ- 

 ence between this example and the third, that there is be- 

 tween a square foot and a cubic foot ?" 



* I said " a given resistence." The word, given, (the omission of which wag 

 doubtless accidental,) is not important as it respects the purpose for which Mr. 

 Quinby made the quotation, but it is essential in the connection in which it 

 stands in my piece. 



