The President of the State Society for this year is Mr. JOHN DELAFIELD, long a master spirit among our Wall-street financiers, and for some years President of the Phenix bank. He was finally swamped by the rascality of the State of Illinois in virtually repudiating her public debt, whereby Mr. Delafield, who had long acted as her financial agent in New-York, and had staked his fortune on her integrity, was reduced from affluence to need. Nothing daunted by this reverse, he promptly transferred his energies from finance to agriculture, taking hold of a large farm in Seneca County, near the beautiful village of Geneva; and on this farm he soon proved himself one of the best practical agriculturists in our State. Before he had been five years on the soil, he was already teaching hundreds of life-long cultivators, by the quiet force of his successful example, how to double the product of their lands and more than double their annual profits. His enlightened and admirable husbandry has finally called him to the post he now occupies--one not inferior in true dignity and opportunity for usefulness to that of Governor of the State. And this is a fair specimen of the elasticity of the American character and its capacity for adapting itself to any and every change of circumstances. [Illustration: INTERIOR OF THE FAIR.] The Annual Address at this Fair was delivered by the Hon. STEPHEN A. DOUGLAS, now U. S. Senator from Illinois, and a very probable "Democratic" candidate for next President of the United States. It was an able and well enunciated discourse, devoted mainly to political economy as affecting agriculture, taking the "free trade" view of this important and difficult subject, and evidently addressed quite as much to southern politicians as to New-York farmers; but it embodied many practical suggestions of decided force and value. This address has already received a very wide circulation.