his brother remained to pursue their studies. Here Boyle resumed the mathematics, in which he had been initiated at Eton.

An anecdote, which explains the cause of his first attention to mathematical subjects, ought not to be passed over in silence; as it indicates not merely the early developement of his reasoning powers, but exhibits in a striking manner, a general and important fact in educa tion. Boyle, when at school, and before he was ten years of age, was so seriously attacked with an ague, that it was thought necessary to suspend his studies; or, at least, to allow him to please his own fancy in the choice of books. He chose Romances, which produced such dissipation of thought and unsettledness of mind, that even on the recovery of his health, he found it difficult to fix his attention to any one subject. To cure this mental disease, he resorted to an expedient, which will excite astonishment, if we consider his tender years. He applied forcibly to the extraction of the square and cube roots, and the solution of algebraical equations. This had the desired effect. It moreover gave a permanent direction to his talents, and was the embryo of that great birth of philosophical discoveries he

subsequently brought forth, and by which his name has become immortal.

He quitted Geneva in 1641, and passing through Switzerland and the country of the Grisons, entered Lombardy; and pursuing his rout through Bergamo, Brescia, and Verona, arrived at Venice, where having staid a short time, he returned to the continent and spent the winter at Florence. During his stay in this city, the famous Galileo died at a village in the vicinity. He thence visited Rome, Leghorn, and Genoa; and in 1644, he with his brother returned to England.

Boyle was one of the first members of that society styled by him the invisible, by themselves, the philosophical college, who, after the restoration, were incorporated under the title. of the Royal Society. In 1654, he took up his residence at Oxford, on account of the various adaptations of the place to retirement, study, and philosophical intercourse. It occasioned also the removal of the invisible college, from London to that university. During his residence here, he invented the air-pump. He finally settled, however, in London, where he died in 1691.

The writings of Boyle are very voluminous;

the greater part on subjects of mechanical philosophy; and not a few on other branches of knowledge. The following will be found a tolerably correct list, exclusive of his numerous papers in the Phil. Trans. His first work of any importance was that subsequent to his discovery of the air pump, entitled,

1. New Experiments touching the Spring of the Air. Published shortly after the restora

tion, in 1660.

2. Physiological Essays, and other Tracts, 1661.

3. The Sceptical Chemist, 1661.

4. Considerations on the Usefulness of Experimental Natural Philosophy, 1663.

5. Experiments and Considerations upon Colours; to which was added, a Letter, containing, Observations upon a Diamond that shines in the dark.

6. Considerations on the Style of the Holy Scriptures.

7. Occasional Reflections on several Subjects; to which is prefixed, a Discourse concerning the Nature and Use of such kind of Writings, 1665.

8. Experiments and Observations relative

to an experimental History of Cold, with several Pieces thereunto annexed, 1665.

9. Hydrostatical Paradoxes, made out by new Experiments, for the most part physical and easy, 1666.

10. The Origin of Forms and Qualities, ac'cording to Corpuscular Philosophy, illustrated by Experiments, 1666.

11. Continuation of new Experiments, touching the Spring and Weight of the Air; to which is added, a Discourse of the Atmospheres of consistent Bodies, 1669.

12. Of the Cosmical Qualities of Things, 1670.

13. Considerations on the Usefulness of Experimental and Natural Philosophy, the second part, 1671.

14. A Collection of Tracts upon several useful and important points of Practical Philosophy, 1671.

15. Essay about the Origin and Virtue of Gems, 1672.

16. A Collection of Tracts touching the Relation between Flame and Air, 1672.

17. Essays on the strange Subtlety, great Efficacy, and determinate Nature of Effluvia;

to which were added, variety of Experiments on other Subjects, 1673.

18. A Collection of Tracts on the Saltness of the Sea, the Moisture of the Air, the natural and præternatural State of Bodies; to which is prefixed, a Dialogue concerning Cold, 1674.

19. A Collection of Tracts, comprehending some Suspicions about hidden Qualities of the Air; Animadversions upon Mr. Hobbes's Problem about a Vacuum; a Discourse of the Cause of Attraction by Suction, 1674.

20. In 1675, he printed, Considerations about the Reconcileableness of Reason and Religion, by T. E. a Layman; to which was annexed, a Discourse about the Possibility of the Resurrection, by Mr. Boyle.—Both these were written by Boyle; the signature of the first being merely the final letters of his name.

21. An Experimental Discourse of Quicksilver growing hot with Gold. Printed in the Philosophical Transactions, 1675.

22. Experiments and Notes about the Mechanical Origin of particular Qualities, 1676.

23. Observations on an artificial Substance that shines without any preceding Illustration, 1678.