On his way home from Washington, in March, 1837, more than three years before, he had made a speech at Niblo’s Garden in New York,—­the greatest purely political speech which he ever delivered.  He then reviewed and arraigned with the greatest severity the history of Jackson’s administration, abstaining in his characteristic way from all personal attack, but showing, as no one else could show, what had been done, and the results of the policy, which were developing as he had predicted.  He also said that the worst was yet to come.  The speech produced a profound impression.  People were still reading it when the worst really came, and the great panic broke over the country.  Mr. Webster had, in fact, struck the key-note of the coming campaign in the Niblo-Garden speech of 1837.  In the summer of 1840 he spoke in Massachusetts, New York, Pennsylvania, and Virginia, and was almost continually upon the platform.  The great feat of 1833-34, when he made sixty-four speeches in the Senate on the bank question, was now repeated under much more difficult conditions.  In the first instance he was addressing a small and select body of trained listeners, all more or less familiar with the subject.  In 1840 he was obliged to present these same topics, with all their infinite detail and inherent dryness, to vast popular audiences, but nevertheless he achieved a marvellous success.  The chief points which he brought out were the condition of the currency, the need of government regulation, the responsibility of the Democrats, the miserable condition of the country, and the exact fulfillment of the prophecies he had made.  The argument and the conclusion were alike irresistible, but Mr. Webster showed, in handling his subject, not only the variety, richness, and force which he had displayed in the Senate, but the capacity of presenting it in a way thoroughly adapted to the popular mind, and yet, at the same time, of preserving the impressive tone of a dignified statesman, without any degeneration into mere stump oratory.  This wonderful series of speeches produced the greatest possible effect.  They were heard by thousands and read by tens of thousands.  They fell, of course, upon willing ears.  The people, smarting under bankruptcy, poverty, and business depression, were wild for a change; but nothing did so much to swell the volume of public resentment against the policy of the ruling party as these speeches of Mr. Webster, which gave character and form to the whole movement.  Jackson had sown the wind, and his unlucky successor was engaged in the agreeable task of reaping the proverbial crop.  There was a political revolution.  The Whigs swept the country by an immense majority, the great Democratic party was crushed to the earth, and the ignorant misgovernment of Andrew Jackson found at last its fit reward.  General Harrison, as soon as he was elected, turned to the two great chiefs of his party to invite them to become the pillars of his administration.  Mr. Clay declined any cabinet office, but Mr. Webster, after some hesitation, accepted the secretaryship of state.  He resigned his seat in the Senate February 22, 1841, and on March 4 following took his place in the cabinet, and entered upon a new field of public service.