. . .s a great merit, for things present themselves through it as they appear to the naked eye, and not upside down as is the case with most of the great telescopes.

In 1663, his book entitled Optica Promota, which contained a description of his telescope, was published in London, and thither Gregorie went, hoping that by the assistance of a practical workman he might realise his ideal.

His book had been much read by mathematicians, and amongst others by John Collins, the Secretary to the Royal Society. We can picture then the mutual pleasure with which these two men met. It was in an alehouse, where possibly the jolly tavern keeper took the Aberdonian through the fumes of his stuffy parlour, and presented him to Master Collins as a likely friend for him; anyway, this was the beginning of a life-long friendship, and Collins, who had realised at once what a possibility lay in the proposed reflecting telescope, determined to have . . . Read More