STATE HORTICULTURAL SOCIETY. 1 95 



MR. tick's remarks ON MR. MANNING'S ESSAY. 



Air. President., The excellent paper just read, contains many sugges- 

 tions aflbrding food for thought, and deserving tlie most serious consid- 

 eration ; it also states certain physical facts, which can be satisfactorily 

 explained by the operation of well known physical laws. I will instance 

 of these latter, the fact that forest timber always shows a higher tempera- 

 ture than surrounding objects. The essay truly says, no adequate explan- 

 ation has been given to account for this foct, though it is generally 

 supposed to be owing to inherent specific heat. 



In this fact itself, we may find the elements of a universal law of the 

 physical world, whose knowledge may be of transcendent importance to 

 us in our co-operation with Nature, for securing to ourselves the greatest 

 possible amount of comfort and prosperity flowing from an ameliorated 

 climate. Upon it may depend the solution of the problem, whether we 

 can close the back door against the intrusions of those arctic storms, that 

 now often sweep, in winter, with such fury and destructive violence 

 from the north and northwest over the entire valley of the Mississippi. 

 We ought then to investigate the nature and cause of this fact, and not 

 remain satisfied by accounting for it by an untenable hypothesis. Hold- 

 ing as I do the opinion that it can be shown, incontestibly, that the higher 

 specific temperature of forest trees than surrounding objects is the nor- 

 mal and necessary- result of a great universal law, I undertake the task of 

 explaining it. 



But before doing so, it is necessary to state the facts, so distinctly and 

 circumstantially that their characteristics will stand out in bold relief. 



Some six or seven years ago I read somewhere (perhaps in the 

 Annual ReporL of the Maine State Board of Agriculture), that certain: 

 experiments had been made in the forests of that state, to ascertain the 

 relative temperature in winter, of different kinds of trees. For this pur- 

 pose thermometers were inserted in auger holes bored in growing trees, 

 both deciduous and evergreen, and the holes closed. When the weather 

 was intensely cold the thermometers were examined, and those in ever- 

 greens invariably showed a higher temperature by from 8 to 10 degrees, 

 than those in deciduous; and that the difference in favor of the ever- 

 greens increased as was the increment of the force of the wind. These 

 facts show two things : first, a difference; and secondly, a variation of 

 difference under changed conditions. It therefore overturns the 

 hypothesis, that inherent specific heat is -the sole cause of the 

 higher temperature of trees; for if it were, then although there 

 might be a difference in specific heat between different kinds of 

 trees, yet this difference would remain invariable imder all conditions^ 

 It is not then to an empirical, but to some universal law of Nature that 

 we must look for a solution of the problem. In the conservation, cor- 

 relation, persistence, and equivalence of the physical forces, we find this 

 great law. Although this law is now generally accepted by both physi- 

 cists and scientists, yet it is not as generally applied to the elucidation of 

 physical phenomena as it should be and must be, if we are ever to be 



