Principles and Practice of Horticulture, 535 



laws that plants grow, and that all cultivation, unless found- 

 ed on these principles, must be uncertain and unsatisfactory. 



The cultivator of the soil has constantly to contend with 

 various incidents which go far to counteract his best efforts; 

 weather, — climate, — soil, — all have a material influence upon 

 his operations. Insects and vermin of various sorts have to 

 be contended with, forming a phalanx of formidable oppo- 

 nents, requiring skill, intrepidity, and a knowledge of their 

 habits and natures, to enable him to adopt measures for their 

 extermination. Sudden and extreme changes of weather are 

 too well known to be often the cause of ruinous disappoint- 

 ment, and, if the location and other physical circumstances 

 are bad, success will be limited, although his management 

 may be unimpeachable. 



Keeping these things in view, it is plain that a thorough 

 knowledge of the fundamental laws, the definite and immuta- 

 ble principles on which these physical sciences are founded, 

 is of the utmost importance to the cultivator of the soil, en- 

 abling him to see the rationale of his operations, and contend, 

 with some chance of success, against the many evils with 

 which he is assailed. 



Practice without science may be compared to a ship with- 

 out either compass or rudder — the sails may be unfurled, and 

 every advantage taken to catch the favoring breeze, but the 

 chances of reaching the desired haven are few ; so, seed may 

 be sown, trees planted, and all the minor details performed, 

 but, without science (the compass,) success will result more 

 from accident than certainty ; and the probability of a suc- 

 cessful termination will, in both cases, be very much alike. 



On the other hand, there is not wanting those who, con- 

 fiding solely on theoretical knowledge, are as little inclined 

 to listen to the experience of practice, as the others are to the 

 dictates of science. It is needless to say, the one extreme is 

 as bad as the other, and it is to the intelligent, practical man 

 that we must look for the useful application in art of the 

 demonstrations of science ; and although the truths that sci- 

 entific research has already revealed, may be looked upon as 

 only faint glimmerings of mighty principles yet to be di- 

 vulged, if the light that has already been thrown upon the 

 economy of vegetable life was more generally difl'used, many 



