and dental science was extensive. Dr. Hayden was a surgeon of Maryland troops in the battle of North Point in 1814. He received the honorary degree of M. D. from Jefferson college in 1837, and from Maryland medical university in 1840. He was the founder and incorporator, and first president, of Baltimore college of dental surgery, and its first professor of dental pathology and physiology from 1839 till his death. He was also founder and president until his death of the American society of dental surgery, and a founder and vice-president of the Maryland academy of sci- ence and literature. He was a member of many other learned societies, and published " Geological Essays, or an Inquiry into Geological Phenomena to be found in Various Parts of America " (Balti- more, 1820), which Benjamin Silliman said " should be a text-book in all our schools," and papers, in- cluding li New Method of preserving Anatomical Preparations," in the "American Medical Record " of 1822 ; " Notice of a Singular Ore of Cobalt and Manganese," in " Silliman's Journal " (1822) ; " The Bare Hills near Baltimore," in " Silliman's Jour- nal " for 1832 ; and " Silk Cocoons," in the " Jour- nal of the American Silk Company " (1839).
HAYES, Augustus Allen, chemist, b. in Wind-
sor, Vt., 28 Feb., 1806 ; d. in Brookline, Mass., 21
June, 1882. He was graduated at Capt. Par-
tridge's military academy at Norwich, Vt., in 1823,
and then studied chemistry under James P. Dana.
Subsequently he became assistant professor of
chemistry in the New Hampshire medical college,
but settled in Boston in 1828, where he devoted
himself to chemical investigations, filling also suc-
cessively the posts of director of an extensive fac-
tory of colors and chemical products in Roxbury
and of consulting chemist to some of the most
important dyeing, bleaching, gas, and iron and
copper smelting establishments in New England.
Among his early researches is that begun in 1825
for the purpose of determining the proximate com-
position of various American medicinal plants,
which resulted in his discovery of the organic alka-
loid sanguinaria, a compound remarkable for the
brilliant colors of its salts. Later he conducted
an elaborate investigation upon the economical
generation of steam and the relative value of fuels,
which, in 1838, led to a novel arrangement of
steam-boilers. He was the first to suggest the ap-
plication of the oxides of iron in refining pig-iron,
and still earlier the refining of copper was, under
his direction, rendered much shorter and more
certain by the introduction of scales of oxide of
copper. Among his other original investigations
are those in relation to the chemical decomposition
of alcohol by chlorine and the formation of chloro-
form, on the action of alcohol on the human sys-
tem, on the formation, composition, and specific
differences of the varieties of guano, and a memoir
on the difference in the chemical constitution and
action of sea waters on and below the surface, on
soundings, and at the entrance of rivers, being
part of an investigation executed under a commis-
sion from the navy department to examine and re-
port on the subject of copper and copper sheath-
ing as applied in the construction of national ves-
sels. In 1859-'60, while investigating the water
supply of Charlestown, Mass., he found that the
deep water of Mystic pond was far less pure than
the surface water, and proved that a copper strip
or wire passing vertically through two masses of
water slightly unlike in composition would become
polarized and exhibit electrolytic action. This
mode of testing the exact limits of the impure
water was applied under his direction, and a large
number of observations on this and other masses
of water have proved the practical value of this
test. After the beginning of the civil war, Dr.
Hayes called public attention to the uncertainty of
the foreign supply of saltpetre and the necessity of
domestic production. His efforts resulted in the
manufacture of a very pure product for the navy
by a novel process from sodium nitrate by the ac-
tion of potassium hydroxide. Later he spent some
time abroad, and on his return published a paper
" On the Cause of the Color of Lake Leman, Ge-
neva," and also one " On the Red Oxide of Zinc
in New Jersey." For many years he held the of-
fice of state assayer of Massachusetts, and in 1846
received the honorary degree of M. D. from Dart-
mouth. He was a member of scientific societies in
the United States, and contributed numerous pa-
pers of technical value to their proceedings and to
the " American Journal of Science."
HAYES, Catharine, vocalist, b. in Limerick,
Ireland, in 1825; d. in Sydenham, England, 11
Aug., 1861. She early displayed a good voice, at
the age of sixteen was placed under the tuition of
Signor Sapio, an eminent vocal instructor in Dub-
lin, and during her course with him made her first
appearance at a public concert. She studied in the
school of Manuel Garcia in Paris in 1844-'6, and
in the autumn of 1845 appeared at Marseilles in
" I Puritani." In 1846 she sang at Milan with
much success. In 1849 she appeared at the Royal
Italian opefra, Covent Garden, London. Shortly
afterward the success of Jenny Lind during her
career in this country attracted attention, and Miss
Hayes visited the United States in 1851. She
sang in numerous concerts, oratorios, and ballad
entertainments with success, extending her tour to
the principal cities of the Union and British
America. Her stay in this country lasted eighteen
months, during which time she was married to a
Mr. Bushnell. She then visited in succession
South America, the Sandwich and other Polyne-
sian islands, Australia, and the East Indies. Re-
turning to England in 1855, she made her re-en-
trance in Italian opera at Covent Garden theatre,
and soon afterward closed her professional career.
Later she and her husband quietly spent several
years in California and returned to England with
an ample fortune. Catharine Hayes had a remark-
ably full, sympathetic mezzo-soprano voice, which
she used with great effect in slow movements and
in ballads. Her rendering of Bellini's " Casta
Diva " and of Crouch's " Kathleen Mavourneen "
could scarcely be excelled.
HAYES, Isaac Israel, arctic explorer, b. in Chester county, Pa., 5 March, 1832 ; d. in New York city, 17 Dec, 1881. He was graduated in medicine at the University of Pennsylvania in 1853, and sailed as surgeon of the second Grinnell expedition in search of Sir John Franklin, better known, from its commander, as the Kane expedition. (See Kane, E. K.) Dr. Hayes proved an energetic and valuable coadjutor of Kane. In addition to his duties as surgeon and naturalist, he made a short trip on the glacier, inland from Van Rensselaer harbor, and assisted in laying out
depots in the autumn of 1853. In May, 1854, he crossed Kane sea, and was the first civilized man to place foot on Grinnell Land, along the coast of which he travelled to Cape Frazer, about 79° 45' north latitude. The " Advance " was frozen in on 9 Sept., 1853, and remained so in the summer of 1854. Dr. Kane turned toward Beechy island by
boat for assistance, but was obliged by the condition of the ice to return to his old winter-quarters. On 28 Aug., 1854, Dr. Hayes and eight others left
