In the third voyage Gulliver continues his adventures in Laputa, and this is a satire upon all the scientists and philosophers. Laputa is a flying island, held up in the air by a loadstone; and all the professors of the famous academy at Lagado are of the same airy constitution. The philosopher who worked eight years to extract sunshine from cucumbers is typical of Swift's satiric treatment of all scientific problems. It is in this voyage that we hear of the Struldbrugs, a ghastly race of men who are doomed to live upon earth after losing hope and the desire for life. The picture is all the more terrible in view of the last years of Swift's own life, in which he was compelled to live on, a burden to himself and his friends. In these three voyages the evident purpose is to strip off the veil of habit and custom, with which men deceive themselves, and show the crude vices of humanity as Swift fancies he sees them. In the fourth voyage the merciless satire is carried out to its logical conclusion. This brings us to the land of the Houyhnhnms, in which horses, superior and intelligent creatures, are the ruling animals. All our interest, however, is centered on the Yahoos, a frightful race, having the form and appearance of men, but living in unspeakable degradation. The _Journal to Stella_, written chiefly in the years 1710-1713 for the benefit of Esther Johnson, is interesting to us for two reasons. It is, first, an excellent commentary on contemporary characters and political events, by one of the most powerful and original minds of the age; and second, in its love passages and purely personal descriptions it gives us the best picture we possess of Swift himself at the summit of his power and influence. As we read now its words of tenderness for the woman who loved him, and who brought almost the only ray of sunlight into his life, we can only wonder and be silent. Entirely different are his _Drapier's Letters_, a model of political harangue and of popular argument, which roused an unthinking English public and did much benefit to Ireland by preventing the politicians' plan of debasing the Irish coinage. Swift's poems, though vigorous and original (like Defoe's, of the same period), are generally satirical, often coarse, and seldom rise above doggerel. Unlike his friend Addison, Swift saw, in the growing polish and decency of society, only a mask for hypocrisy; and he often used his verse to shock the new-born modesty by pointing out some native ugliness which his diseased mind discovered under every beautiful exterior.