AMERICAN INSTITUTE. 455 



Professor Hedriclc. — Any thing, or force, which operating in time pro- 

 tluces a phenomenon, is a cause. The leaf which precedes the fruit is not 

 the cause of it. Simple antecedence is not enough to establish the relation 

 of cause and effect. Causes are the indestructible things in nature — the 

 absolute entities — -mind and matter — while effects are the phenomena, or 

 changes of form, which occur in material things. 



Mr. Ti!lman.— We employ in the business of life a great variety of 

 forces or sources of power, but, I think, we may trace most of them to the 

 sun as the ultimate material cause. To the actions of the sun is due the 

 force operative in all forms of water powers. The force of the wind, so 

 valuable in navigation and potent in forms of wind-mills, is due to the same 

 climate clause. We sec its operation daily in the tides. To the action of 

 the sun is due the force which, in the Spring, quickens the vegetable world 

 into universal life, and which stores the fruits with force to sustain the 

 lives of men and animals. Carbon, which, in the form of fuel, is the great 

 source of mechanical force in modern times, is principally obtained from 

 the coal deposited, if geology be true, in obedience to the sun's action, for 

 it is the remains of primeval forests which derived their growth and vital 

 force from the sun. According to Laplace, the very earth itself is from 

 the sun, and all its motions are due to his action. And here we are lead 

 forcibly to consider that no power once in existence is destroyed. 



Mr. Stetson.— I fully endorse the idea that all force comes fiom the sun, 

 though there is nothing to prevent us looking higher than the sun to the 

 ultimate cause of all things. All mechanical agency, whether from the 

 steam engine or animal power, is obtained from the decomposition of mate- 

 rial substances, vegetable and mineral, and all causes of decomposition or 

 chemical action can be traced to the sun as the iraparter of the power. 

 People have ascribed all pow3r to one or more gods, and we can not won- 

 der that the Persians should select as their god, the sun ; for if we enquire 

 why trees and plants grow — those sources of food and shelter for man — we 

 are compelled to stop with the sun; we can not trace the relation of cause 

 and effect farther, though our imagination may lead us to a higher ultimate 

 cause. 



Mr. Tillman.- — The whole of space is filled with ether, which is the vehi- 

 cle of force, and as force goes off from any centre through the ether, it may 

 in like manner return through the same medium, and so not be lost. 



Dr. Reuben. — When we speak of causes and forces, we ought to define 

 those items distinctly. All words, in common language, are used indeter- 

 minately, but in scientific discussion they ought to be made quite as deter- 

 minate as possible. Power and force are not identical. Power implies 

 force in action. Power is any agency in creation. Niagara falls would be 

 a motive power. But when we inquire into causes we are launched into 

 the sea of metaphysics. To us any thing that is sufficient in giving a result 

 is a cause. In this sense, then, chemical affinity is the first great cause 

 that we find in operation. Added to this, gravitation gives us the explana- 

 tion of the system of the Universe. In tracing the nebular theory we find, 



