vin in 1848 and 1849. Fortunately his manuscripts had been preserved,
and extracts were appended to a reprint of his _Puissance motrice_ by
his brother, L.H. Carnot, in 1878. These show that he had not only
realized for himself the true nature of heat, but had noted down for
trial many of the best modern methods of finding its mechanical
equivalent, such as those of J.P. Joule with the perforated piston and
with the friction of water and mercury. Lord Kelvin's experiment with a
current of gas forced through a porous plug is also given. "Carnot's
principle" is fundamental in the theory of thermodynamics (q.v.).

CARNOUSTIE, a police burgh and watering-place of Forfarshire, Scotland.
Pop. (1901) 5204. It lies on the North Sea, 10-3/4 m. E.N.E. of Dundee by
the North British railway. Bathing and golfing are good. Barry Links, a
triangular sandy track occupying the south-eastern corner of the shire,
are used as a camping and manoeuvring ground for the artillery and
infantry forces of the district, and occasionally of Scotland. Its most
extreme point is called Buddon Ness, off which are the dangerous shoals
locally known as the Roaring Lion, in consequence of the deep boom of
the waves. On the Ness two lighthouses have been built at different
levels, the lights of which are visible at 13 and 16 m.

CARNUNTUM ([Greek: Karnous] in Ptolemy), an important Roman fortress,
originally belonging to Noricum, but after the 1st century A.D. to
Pannonia. It was a Celtic town, the name, which is nearly always found
with K on monuments, being derived from _Kar, Karn_ ("rock," "cairn").
Its extensive ruins may still be seen near Hainburg, between
Deutsch-Altenburg and Petronell, in lower Austria. Its name first occurs
in history during the reign of Augustus (A.D. 6), when Tiberius made it
his base of operations in the campaigns against Maroboduus (Marbod). A
few years later it became the centre of the Roman fortifications along
the Danube from Vindobona (Vienna) to Brigetio (O-Szony), and (under
Trajan or Hadrian) the permanent quarters of the XIV legion. It was also
a very old mart for the amber brought to Italy from the north. It was
created a municipium by Hadrian (Aelium Carnuntum). Marcus Aurelius
resided there for three years (172-175) during the war against the
Marcomanni, and wrote part of his _Meditations_. Septimius Severus, at
the time governor of Pannonia, was proclaimed emperor there by the
soldiers (193). In the 4