It was the steady rise of this tide of opposition in which Cromwell saw the doom of his cause. That it could permanently be upheld by the sword he knew to be impossible. What he had hoped for was the gradual winning of England to a sense of its worth. But every day the current of opinion ran more strongly against it. The army stood alone in its purpose. Papist and sceptic, mystic and ceremonialist, latitudinarian and Presbyterian, all were hostile. The very pressure of Cromwell's system gave birth to new forms of spiritual and intellectual revolt. Science, rationalism, secularism, sprang for the first time into vivid life in their protest against the forced concentration of human thought on the single topic of religion, the effort to prison religion itself in a system of dogma, and to narrow humanity with all its varied interests within the sphere of the merely spiritual. Nothing is more significant, though to Cromwell nothing would have been more unintelligible, than the simple story which tells us how from the vexed problems, political and religious, of the times, men turned to the peaceful study of the natural world about them. Bacon had already called men with a trumpet-voice to such studies; but in England at least Bacon stood before his age. The beginnings of physical science were more slow and timid there than in any country of Europe. Only two discoveries of any real value came from English research before the Restoration: the first, Gilbert's discovery of terrestrial magnetism in the close of Elizabeth's reign; the next, the great discovery of the circulation of the blood, which was taught by Harvey in the reign of James. Apart from these illustrious names England took little share in the scientific movement of the Continent; and her whole energies seemed to be whirled into the vortex of theology and politics by the Civil War.