and assistance I can lay a claim.”[378] So far was Nicolas V. from being offended by the freedom with which Poggio in this oration reminded him of his duty, that he testified his esteem for his monitor by conferring upon him very liberal presents. So noble indeed was the munificence of the pontiff, that Poggio declared, that in consequence of the generosity of this enlightened Mæcenas, he regarded himself as at length reconciled to fortune.[379] The genial warmth of the sunshine of prosperity did not, however, cause Poggio to relax in his mental exertions. On the contrary, the prospect of honour and profit, and the spirit of emulation excited by the success of his learned competitors, stimulated him, notwithstanding the advanced period of life to which he had now attained, to pursue his studies with renewed assiduity. He had for a long space of time been occasionally employed in collecting materials for a Dialogue _On the Vicissitudes of Fortune_. These materials he now began to arrange, and having finished and carefully corrected his work, he submitted it to the public inspection, [A. D. 1447.] under the patronage of the pontiff, to whom he respectfully inscribed it by a dedicatory epistle. In this address he descanted on the utility of history, and pointed out the moral tendency of his Dialogue, which, by demonstrating the instability of human things, would repress the confidence of pride and the aspiring views of ambition. He remarked, that the subject of the work which he now presented to his patron was nearly allied to that of the Dialogue _On the Unhappiness of Princes_, which he had formerly dedicated to him, and that it consequently had a peculiar claim to his protection. He moreover reminded his illustrious friend, that though in his ecclesiastical capacity he might be regarded as beyond the reach of misfortune, yet as the sovereigns of the temporal dominions of the church, the pontiffs themselves are not exempted from the common lot of mortality; and expressed his persuasion, that by becoming acquainted with the distresses of his predecessors, he would learn the salutary lesson of caution.[380] The opening of the Dialogue _On the Vicissitudes of Fortune_ is singularly grand and interesting. It exhibits Poggio and his confidential associate, Antonio Lusco, fatigued by the inspection of the remains of Roman magnificence, reposing themselves amidst the venerable ruins of the capitol, which building commands a prospect of almost the whole extent of the city. After Antonio has gazed for a few minutes upon the waste of years, he exclaims with a sigh, “How unlike, Poggio! is this capitol to that which Maro sung, as— “Chang’d from horrid thorn to glittering gold.”