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 Milan. In command of his legion he played an important part in the war in Italy, entered Rome in May 1798, and distinguished himself greatly at the Trebbia (June 19, 1799), and in other battles and combats of 1799–1801. After the peace of Amiens he passed, as general of division, into the service of the Italian republic. Summoned by Napoleon in 1806 to promote a rising in Poland, he organized several divisions of Poles, and distinguished himself at Danzig and at Friedland. In 1809 he served in the Polish campaign and in 1812 he commanded a Polish division in the Grande Armée, being wounded at the passage of the Beresina. He fought under Marmont at the battle of Leipzig (1813), and in the following year returned to Poland. He was one of the generals entrusted by the tsar with the reorganization of the Polish army, and was named in 1815 general of cavalry and senator palatine of the new kingdom of Poland. He retired, however, in the following year, to his estates in Posen. General Dombrowski died at his seat of Wina-Gora in Posen on the 26th of June 1818. He wrote several military historical works in the Polish language.

 DOME (Lat domus, house; Ital. duomo, cathedral), an architectural term, derived from a characteristic feature of Italian cathedrals, correctly applied only to a spherical or spheroidal vault, the horizontal plan of which is always a circle. It may be supported on a circular wall, as in the Pantheon at Rome; or on a drum, as in the later Byzantine churches and generally so in the Renaissance styles; or be carried over a square or polygonal area, in which case the base of the dome is connected to the lines of the main wall by pendentives, squinches, corbels or a series of concentric arches, or two of these combined. Its section may be semicircular, pointed, ovoid or segmental; in the latter case it is usually termed a cupola, although the pendentives which carry it continue, on the diagonal lines, the complete spherical dome, as in the entrance vestibule on the south side of the Sanctuary at Jerusalem, attributed to Herod, or in those crowning the bays of the Golden Gateway by Justinian. The dome may be constructed in horizontal courses, as in the “beehive” tombs at Mycenae, with joints radiating to the centre, or a compromise between the two, in a series of small segments of circles, as in the Temple of Jupiter in Diocletian’s palace at Spalato, or again with the lower portion in horizontal courses and the upper portion with arches, as in the Pantheon at Rome.

The dome is probably one of the earliest forms of covering invented by man, but owing probably to its construction in ephemeral materials, such as the unburnt bricks in Chaldaea, there are no examples existing. But in a bas-relief (see, fig. 10), brought by Layard from Kuyunjik, are representations of semicircular and ovoid domes, which show that the feature was well known in Assyria, and as they build domes of the same nature down to the present day and without centring of any kind, it suggests that they may have existed from the remotest ages. The most ancient examples in Europe are those of the “beehive” tombs at Mycenae and elsewhere in Greece, ascribed generally to the 11th century In a sense, they are not true domes, because they are built in horizontal courses of stone, which act like the voussoirs of an arch in resisting the thrust of the earth at the back. This did not exist in the Choragic Monument of Lysicrates or other circular buildings in Greece, because their vertical sections were not portions of circles. For this reason, the conical vault of the Baths in Pompeii is not a dome. The circular Laconicon in the Baths of Titus ( 72) may have been domed, and the great hemicycles in the Thermae must certainly have been roofed with semi-domes.

The earliest Roman domes are those of the great circular halls at Baiae near Naples, described as temples, but really forming part of the immense bathing establishments there, the favourite place of resort of the Romans during the latter part of the Republic. The largest on the east side of the Lake of Avernus, known as the Temple of Apollo, is a circular hall with an internal diameter of 100 ft. Those of Diana, Mercury and Venus at Baiae, were 96, 66 and 60 ft. respectively. The vaults were all built in tufa with horizontal courses in brick and cement. Half of the dome of the Temple of Mercury had fallen down, showing the section to have been nearly that of an equilateral arch. From the fact that there were pierced openings or windows in all these domes, they probably constituted the frigidaria of the baths.

The first example still existing in Rome is that of the Pantheon ( 112), where a circular dome, 142 ft. in diameter, rests on a circular wall, its height being about equal to its diameter. The lower courses of this dome, built in the Roman brick or tile, were, up to the top of the third coffer, all laid in horizontal courses; above that, the construction is not known for certain; externally a series of small arches is shown, but they rested on a shell already built. The so-called Temple of Minerva Medica (now recognized as the Nymphaeum of the Baths of Gallienus, 366) is the next dated example. The Nymphaeum was decagonal on plan, so that small pendentives were required to carry the brick dome.

The domed Laconicon of the Thermae of Diocletian ( 302) still exists as the vestibule of the church of Santa Maria degli Angeli. Of Constantine’s time there are two small domed examples in the tomb of S. Costanza and the Baptistery of the Lateran, both in Rome, and one in the tomb of Galla Placidia at Ravenna (c. 450). From these we pass to the Sassanian domes at Serbistan and Firuzabad, of the 4th and 5th centuries respectively. These were built in brick and rested on square pendentives. In section they were ovoid. In Syria, the dome over the octagonal church at Esra, built in stone and dated 515, is also ovoid, its height being equal to its diameter, i.e. 28 ft. This, as well as the Sassanian domes, was built without centring. The next example is that of the church of Sta Sophia at Constantinople, the finest example existing, both in its conception and execution. It was built by Justinian (537–552) from the designs of Anthemius of Tralles and Isidorus of Miletus. The dome is 104 ft. in diameter, and is carried on pendentives over a square area. The construction is of brick and stone in alternate courses, and the lower part of the dome is pierced with forty windows, which give it an extraordinary lightness. The height from the pavement of the church to the soffit of the dome is 179 ft. No dome of similar dimensions was ever again attempted by the Byzantine architects, and the principal difference in later examples was the raising of the dome on a circular drum pierced with windows.

In order to lighten the dome erected over the church of San Vitale, at Ravenna, it was constructed with hollow cylindrical jars, fitted, the end of one into the mouth of the other; a similar contrivance was adopted in the tomb of the empress Helena (the Torre Pignatiara), the vaults of the Circus of Maxentius on the Via Appia, and the outer aisles of San Stefano, all at Rome, thus dispensing with the buttresses of Sta Sophia.

The domes of the earlier mosques in Cairo were built on the model of Sta Sophia, with windows pierced round the base of the dome and external buttresses between them; these domes were all built in brick coated over with cement or stucco. At a later date, and when built in stone, the upper portion was raised in height and terminated with a point on which a finial was placed. These are the domes inside and outside Cairo, which are carved with an infinity of geometrical patterns interwoven with conventional floral decoration. The upper portion of the dome is very thin, so that there is little weight and comparatively no thrust, and it is to these facts that we probably owe their preservation.

In India, in the “great mosque” of Jama Masjid ( 1560) and the Gol Gumbaz, or tomb of Mahommed Adil Shah ( 1630) at Bijapur, the domes are carried on pendentives consisting of arches crossing one another and projecting inwards, and their weight counteracts any thrust there may be in the dome. It is possibly for a similar reason that in the Jama Masjid of Shah Jahan at Delhi (1632–1638) and the Taj Mahal ( 1630) the domes assume a bulbous form, the increased thickness of the dome below the haunches by its weight served as a counterpoise to any thrust the upper part of the dome might exert. The form is not much to be admired, and when exaggerated, as it is in the churches of Russia, where it was introduced by the Tatars, at times it became monstrous. 