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He was simple, earnest, and companionable, He was entirely free from assumptions of superiority, and, still learning, would listen attentively to the humblest student. He was ready to counsel and instruct, as well as to receive information. He would sit down in my workshop, and see me go through the various technical processes of casting, grinding, and polishing specula for reflecting telescopes.

The rationale of the strength of specula cast in this metal mould system, as compared with the treacherous brittleness of those cast in sand moulds, arises simply from the consolidation of the molten metal pool taking place first at the lower surface, next the metal base of the mould the yet fluid alloy above satisfying the contractile requirements of that immediately beneath it; and so on in succession, until the last to consolidate is the top or upper stratum.

Hopkinson, I mentioned to him that the Abbe Rochon, who discovered the double refracting power in some of the natural crystals, had lately made a telescope with the metal called platina, which, while it is as susceptible of as perfect a polish as the metal heretofore used for the specula of telescopes, is insusceptible of rust, as gold and silver are.

No one has so great a claim on the fruit of my labours; for you inoculated me with the love of star-gazing, and gave me invaluable aid and advice in figuring specula. I daresay you may remember the first occasion on which I saw a reflecting telescope, which was then being tried on the sun in a pattern loft at Patricroft.

His great work, which has been termed "the Encyclopaedia and the Novum Organum of the thirteenth century," discloses an unfettered mind and judgment far in advance of the spirit of the age in which he lived. In addition to this he wrote Compendium Philosophiae, De mirabili Potestate artis et naturae, Specula mathematica, Speculum alchemicum, and other works.

So when we think of this brother and sister sailing away upon an unknown ocean working day after day, night after night, week after week, and month after month, discarding scores of specula which they had worked upon many weary hours in order to get the glass that would serve their purpose we must remove our hats in reverence. God sends great men in groups.

W. Herschel was born at Hanover in 1738, came to England in 1758 as a trained musician, and died in 1822. He studied science when he could, and hired a telescope, until he learnt to make his own specula and telescopes. He made 430 parabolic specula in twenty-one years.

Amongst these was Sir David Brewster, who took a most lively and special interest in all my labours on this subject. In later years I resumed my telescope making enjoyments, as a delightful and congenial relaxation from the ordinary run of my business occupations. I constructed several reflecting telescopes, of sizes from 10-inch to 20-inch diameter specula.

I had also the pleasure of assisting other astronomical friends, by casting and grinding specula for them. Among these I may mention my late dear friend William Lassell, and my excellent friend Warren de la Rue, both of whom have indelibly recorded their names in the annals of astronomical science.

Then you think he does not know who it was?" cried James Brandon, with the air of a man catching at a straw to save himself. "Sure of it," said Sam coolly, as he opened one of the papers and began reading "`Instructions for grinding and polishing specula." He opened another. "`The various modes of mounting telescopes." Throwing this down, he took up a third paper, and read