11. The Honourable Robert Boyle received from Dr. Hook a copy of the "Definition," sent to him with a letter on the subject.
12. Lord Brereton is specially mentioned by Dr. Hook, as being so confirmed in his doubts of the excellence of the Marquis's engine, that he had laid a wager on the subject.
13. Henry Somerset, Lord Herbert, afterwards created first Duke of Beaufort, by Charles II., must have frequently seen the engine in operation. He died in 1699.
14. James Rollock, who wrote a poetic eulogy on the Engine about 1663, speaks of himself as "an ancient servant," having known his lordship forty years, dating back to 1623.[7]
15. Samuel Sorbière visited the works at Vauxhall, and published particulars of the engine he saw there in 1663.
16. Lord John Somerset, the Marquis's eldest brother, appears latterly to have lived at Vauxhall, according to a warrant dated September, 1664; and would certainly be admitted into his brother's confidence.
17. Cosmo the Third, Grand Duke of Tuscany, in his Diary exactly describes the engine he saw at Vauxhall in 1669, "considered to be of greater service to the public than the other machine near Somerset House."
18. Walter Travers, a Roman Catholic priest, names the engine in a letter which he wrote to the Dowager Marchioness of Worcester, in 1670.
19. Dr. Thomas Sprat, F.R.S., published in 1665, a critical work on "M. Sorbière's Voyage into England," and could not therefore be ignorant of the Marquis's engine, as it was named by the French traveller, although Sprat omitted to notice it specially in his own "Observations."