12 INFLUENCE OF CURRENTS IN THE AIR AND IN THE SEA. 



and flowers, and then sink again into their annual slumber ? How is it, also, that wild 

 birds and beasts conform in their habits to the progress of the seasons, and at one time 

 prepare to bring forth their young, and at another anticipate, with a provident foresight, 

 the coming winter ? Those great migrations of fishes that take place at given seasons, 

 and which are even connected with the well-being and wealth of nations, are deter- 

 mined by the occurrence of certain epochs. It is no explanation of these curious facts 

 to say that they depend on other facts like themselves that an animal sleeps by night, 

 because his prey is also asleep ; that a fish migrates at those periods when his instincts 

 tell him that the food on which he lives is abundant. If, in any of these cases, we 

 pass from fact to fact, we uniformly come, at last, to the same conclusion, that all these 

 incidents are directed by astronomical events ; that THE SUN not only determines peri- 

 ods of awakening and sleep, of growth and decay, but that there is also committed to 

 him a control and regulation over all the movements of animated beings on the face of 

 the globe. It is the luminous rays of that distant star which, falling perpendicularly, 

 produce the luxuriant vegetation of tropical regions, and his rays of heat which debili- 

 ~] tate and enervate the human race. It is, in the polar regions, the obliquity of those 

 beams which suffers the ground to be always covered with snow, and makes those in- 

 hospitable countries almost without inhabitants. The trade winds, also, which blow 

 uninterruptedly for ages, carry away towards the poles immense quantities of oxygen 

 gas, which the green parts of plants throw into the atmosphere of the torrid zone. 

 That oxygen is evolved by light, and is then disseminated by heat. In the sea the 

 same influence which thus presides in the air is also at work. The Gulf Stream, 

 which issues from the Mexican waters, with its temperature elevated by solar action, 

 determines the distribution of the Atlantic fishes ; the northern whale avoids its offen- 

 sive warmth, and on its sides shoals congregate which delight in a more genial heat. 

 As it approaches the coasts of Europe, and spreads out into a fan-like form, the va- 

 pours that rise from it give forth their latent heat to the air, and moderate the climates 

 of England and France. The coldness and sterility of corresponding latitudes in 

 America is there replaced by a better temperature, and agriculture, the arts of life, sci- 

 ence and literature, have there reached their greatest perfection. This physical agent, 

 thus eternally but invisibly continuing its operation, produces a thousand events in 

 which its agency is only remotely traced ; nor are those influences limited to mere 

 physical results ; they stand in connexion with the progress of society and the evolu- 

 tion of mind. A full development of the reasoning faculty can only take place where 

 physical circumstances conspire. It is to the climate of England and France that the 

 human race is indebted for the intellect of Newton and Laplace. 



37. In these remote events, which thus originate among the ordinary phenomena of 

 the natural wdfl'd, and strike us forcibly when we trace them, step by step, from their 

 origin to their result, we are prone, at a casual glance, to give too much weight to in- 

 tervening influences, and forget the final cause. Would it be too much to assert that, 

 with returning seasons, periods of vegetation, and the distribution of animated nature, 

 astronomical occurrences likewise direct a thousand of those daily movements which 

 are taking place in every part of the world? There is no harvest which is gathered, 

 no famine which desolates, that has not sprung from an immediate connexion with 



