in optics, owing to its high refractive and small dispersive power.
Sp. gr. 3.521.
Among the celebrated diamonds may be noted the following:— Great Mogul. Found in 1550, in Golconda, and seen by Tavernier.
Weighed 793 carats; cut to 279 carats (carat, 4 grains).
Russian. Taken from a Brahminical idol by a French soldier; sold to the Empress Catherine for £ 90,000 and an annuity of £ 4,000. Weighs 194 carats.
Pitt. Brought from India by Mr. Pitt, the grandfather of the first Earl of Chatham; sold to the Regent Duke of Orleans, in 1717, for £ 135,000. Weighed when rough, 400 carats; cut to 136 1/2 carats.
Napoleon placed it in the hilt of his sword.
Koh-i-noor. Seen by Tavernier in 1665, in the possession of the Great Mogul.
Seized by Nadir Shah, in 1739, at the taking of Delhi.
Became the property of Runjeet Sing.
Captured by the English at the taking of the Punjab.
Presented to the Queen by the East India Company, in 1850; weighed in the rough 800 carats, cut to 186 1
med per hour (4), the duty was 77,358,478.
As reduced to the actual delivery of water, in the reservoir, it was 76,386,262 and 76,584,894 by the two methods respectively.
The following is the duty officially given for the engines cited: —
Brooklyn, No. 1, double-acting beam60,140,700
Belleville (Jersey City), Cornish62,823,300
Hartford (3 experiments), crank58,779,300 to 64,669,400
Brooklyn, No. 3, double-acting beam72,000,000
Cambridge (2 experiments), Worthington double-cylinder, noBrooklyn, No. 3, double-acting beam72,000,000
Cambridge (2 experiments), Worthington double-cylinder, not duplex66,941,100 to 67,574,600
Spring Garden (Philadelphia), Cornish58,905,300
The dity or useful effect of the Cornish pumpingengine has been more closely observed and recorded than that of any other engine.
The duty is reported monthly, and is reduced to tabulated form, from which the yearly report is made out.
The duty of these engines has been gradually improved.
It is estimated by the number of pounds raised one foot high by a bushel of Welsh coals, 94 pounds.
Pounds, 1 foot