After the award of the king's pension, Sir William Herschel fixed his residence at Slough, near Windsor, his family consisting at first of one of his brothers, and his sister, Miss Caroline Herschel, who was his coadjutor and assistant in his computations and reductions, and was also actively employed in astronomical observation, being the discoverer of more than one comet. Herschel married a widow lady, Mrs. Mary Pitt, and left one son, the present Sir John, whose name has long been known to the public as one of the most active and successful adherents of science that our day has produced.
Dr. J. D. Forbes thus sums up the philosophical character of Sir William Herschel:—
"He united, in a remarkable degree, the resolute industry which distinguishes the Germans, with the ardour and constancy which has been thought characteristic of the Anglo-Saxon. From his native country he brought with him the boldness of speculation which has long distinguished it, and it is probable that he had also a vigorous and even poetical imagination. Yet he was ever impatient until he had brought his conjectures to the test of experiment, and observation of the most uncompromising kind. He delighted to give his data a numerical character, and where this was (by their nature) impossible, he confirmed his descriptions by reiterated observation, in different states of weather, with different telescopes, apertures, and magnifying powers; and with praiseworthy fidelity he enabled his readers to form their own judgment of the character of his results, by copious and literal transcripts from his journals."
Herschel died peacefully at Slough, at the advanced age of eighty-three, on the 23rd of August, 1822, only one year after the publication of his latest memoir in the 'Transactions' of the then recently formed Astronomical Society, of which he was the first president.—Sixth Dissertation, by James David Forbes, D.C.L., F.R.S., &c., Encyclopædia Britt., eighth edition.—English Cyclopædia. London, 1856.—Weld's Hist. of Roy. Society.
EDWARD CHARLES HOWARD, F.R.S.
Born May 28, 1774. Died September 28, 1816.
Mr. Howard was born at Darnell, in the parish of Sheffield, and was the third brother of the twelfth Duke of Norfolk. His name has become intimately connected with the manufacture of sugar, from the many improvements which he introduced into the old processes for the refinement of this most important article of commerce, and especially by his invention of the vacuum-pan.
It is related, on the authority of the late Mr. C. Few, that Mr. Howard's attention was drawn towards this subject by Mr. Charles Ellis, who, on the occasion of an immense quantity of West India sugar being in bond, and for which the revenue could find no market, recommended Howard, whose talents as a practical chemist Mr. Ellis was well acquainted with, to try and see if he could not relieve the Government warehouses, by converting the raw sugar into some kind of manure, and thus avoid the duty and render the article saleable. While experimenting for this purpose, Mr. Howard accidentally discovered his process of purifying sugar, for which, in conjunction with certain sugar refiners, he took out patents, and ultimately realized a considerable fortune.
Howard's vacuum-pan was patented in 1812; it depends for its action on the principle that liquids boil at temperatures dependent on the pressures they have to sustain. Thus water, under the ordinary pressure of the atmosphere (30 inches barometer), boils at 212° F., whereas in vacuo it will boil at about 80°; consequently a comparatively low temperature will effect the boiling of sugar-syrup in vacuo, evaporation will proceed far more safely than in the old process of heating the syrup in open pans, and the percentage of waste will be greatly reduced, rendering the manufacture highly profitable in a commercial point of view.