of 80 deg. C. for many hours. A sensitive thermometer having
its bulb immersed in the centre of the cordite shows when the
temperature rises above 80 deg.. Such a rise indicates internal
oxidation or decomposition of the explosive; it is accompanied by an
evolution of nitrogen dioxide, NO2, the depth of colour of which is
noted through a side tube attached to the bulb. As all explosives of
this class would in time decompose sufficiently to give these
indications, time periods or limits have been fixed at which an
appreciable and definite rise in temperature and production of red fumes
indicate relative stability or instability. (W. R. E. H.)

CORDOBA, GONZALO FERNANDEZ DE (1453-1515), Spanish general and
statesman, usually spoken of by the Italianized form of his Christian
name as GONSALVO DE CORDOBA, or as "the Great Captain," was the second
son of Don Pedro Fernandez de Cordoba, count of Aguilar, and of his wife
Elvira de Herrera, who belonged to the family of Enriquez, the
hereditary admirals of Castile, a branch of the royal house. Gonzalo was
born at Montilla near the city of Cordova (Cordoba) on the 16th of March
1453. The father died when he and his elder brother, Don Alonso, were
mere boys. The counts of Aguilar carried on an hereditary feud with the
rival house of Cabra, and the children were carried by their vassals
into the faction fights of the two families. As a younger son Gonzalo
had his fortune to make, but he was generously aided by the affection of
his elder brother, who was very wealthy. War and service in the king's
court offered the one acceptable career outside the church to a
gentleman of his birth.

He was first attached to the household of Don Alphonso, the king's
brother, and upon his death devoted himself to Isabella, afterwards the
queen. During the civil war, and the conflict with Portugal which
disturbed the first years of her reign, he fought under the grand master
of Santiago, Alonso de Cardenas. After the battle of Albuera, the grand
master gave him especial praise, saying that he could always see Gonzalo
to the front because he was conspicuous by the splendour of his armour.
Indeed the future Great Captain, who, as a general, was above all things
astute and patient, could, and habitually did, display the most reckless
personal daring, going into a fight as if he loved it, and having a
shrewd sense that a reputation for intrepidity, a free-handed profusion,
and the personal m