Dupuy de Lôme was designed to fill the commerce-raiding strategy of the Jeune École.
Considered by some the first true armoured cruiser, she was superior to existing British and Italian protected cruisers, especially in her relatively thick steel armour.
She could control the engagement range with her superior speed and her heavy armament of quick-firing guns, all of which were mounted in gun turrets, in marked contrast to her intended opponents who mounted their guns in lightly protected casemates or pivot mounts.

The ship measured 114 metres (374 ft 0 in) between perpendiculars, with a beam of 15.7 metres (51 ft 6 in).
Dupuy de Lôme had a mean draught of 7.07 metres (23 ft 2 in) and displaced 6,301 tonnes (6,201 long tons) at normal load.
At deep load, she displaced 6,682 tonnes (6,576 long tons) and had a metacentric height of only 0.695 metres (2 ft 3.4 in).
This gave the ship a long, slow roll and made her an uncertain gunnery platform.
Her long, cut-away bow resembled a spur-type ram, but was not armoured.
It was reduced in profile to reduce blast damage when the forward guns were fired.
Dupuy de Lôme was fitted with two large military masts.

She had three triple-expansion steam engines, a vertical type for the centre shaft and horizontal types for the outboard shafts.
Each engine drove a single propeller shaft, with propellers 4.2 metres (13 ft 9 in) in diameter on the outboard shaft and a 4.4-metre (14 ft 5 in) propeller on the centre shaft.
Steam for the engines was provided by 11 Amirauté fire-tube boilers and they were rated at a total of 14,000 metric horsepower (10,000 kW).
The ship had a designed speed of 20 knots (37 km/h; 23 mph), but during sea trials on 2 April 1895 the engines only produced 13,186 metric horsepower (9,698 kW) that gave a maximum speed of 19.73 knots (36.54 km/h; 22.70 mph).
Dupuy de Lôme carried up to 1,080 tonnes (1,060 long tons; 1,190 short tons) of coal and could steam for 4,000 nautical miles (7,400 km; 4,600 mi) at a speed of 12.5 knots (23.2 km/h; 14.4 mph).

Dupuy de Lôme's main armament consisted of two 45-calibre Canon de 194 mm Modèle 1887 guns that were mounted in single gun turrets, one on each broadside amidships.
Her secondary armament comprised six 45-calibre Canon de 164 mm Modèle 1887 guns, three each in single gun turrets at the bow and stern.
The three turrets at the stern were all on the upper deck and could interfere with each other.
For anti-torpedo boat defence, she carried ten 47-millimetre (1.9 in) and four 37-millimetre (1.5 in) Hotchkiss guns.
She was also armed with four 450-millimetre (17.7 in) pivoting torpedo tubes; two mounted on each broadside above water.

The whole side of the ship was protected by 100 millimetres (3.9 in) of steel armour, from the bottom edge of the protective deck 1.38 metres (4 ft 6 in) below the waterline to the edge of the weather deck.
The curved protective deck had a total thickness of 30 millimetres (1.2 in) and did not rise above the ship's waterline.
Protecting the boiler rooms, engine rooms, and magazines below it was a splinter deck 8 millimetres (0.31 in) thick.
The space between the protective and splinter decks could be filled with coal to increase the effective thickness of the ship's armour.
It was very cramped there and the coal was very difficult to access.
A watertight internal cofferdam, filled with cellulose, ran the length of Dupuy de Lôme from the protective deck to a height of 1 metre (3 ft 3 in) above the waterline.
Below the protective deck the ship was divided by 13 watertight transverse bulkheads with three more above the protective deck.
The ship's conning tower was protected by 125 mm (4.9 in) and her turrets by 100 mm of armour.
Dupuy de Lôme was designed to fill the commerce-raiding strategy of the Jeune École. Considered by some the first true armoured cruiser, she was superior to existing British and Italian protected cruisers, especially in her relatively thick steel armour. She could control the engagement range with her superior speed and her heavy armament of quick-firing guns, all of which were mounted in gun turrets, in marked contrast to her intended opponents who mounted their guns in lightly protected casemates or pivot mounts.
The ship measured 114 metres (374 ft 0 in) between perpendiculars, with a beam of 15.7 metres (51 ft 6 in). Dupuy de Lôme had a mean draught of 7.07 metres (23 ft 2 in) and displaced 6,301 tonnes (6,201 long tons) at normal load. At deep load, she displaced 6,682 tonnes (6,576 long tons) and had a metacentric height of only 0.695 metres (2 ft 3.4 in). This gave the ship a long, slow roll and made her an uncertain gunnery platform. Her long, cut-away bow resembled a spur-type ram, but was not armoured. It was reduced in profile to reduce blast damage when the forward guns were fired. Dupuy de Lôme was fitted with two large military masts.
She had three triple-expansion steam engines, a vertical type for the centre shaft and horizontal types for the outboard shafts. Each engine drove a single propeller shaft, with propellers 4.2 metres (13 ft 9 in) in diameter on the outboard shaft and a 4.4-metre (14 ft 5 in) propeller on the centre shaft. Steam for the engines was provided by 11 Amirauté fire-tube boilers and they were rated at a total of 14,000 metric horsepower (10,000 kW). The ship had a designed speed of 20 knots (37 km/h; 23 mph), but during sea trials on 2 April 1895 the engines only produced 13,186 metric horsepower (9,698 kW) that gave a maximum speed of 19.73 knots (36.54 km/h; 22.70 mph). Dupuy de Lôme carried up to 1,080 tonnes (1,060 long tons; 1,190 short tons) of coal and could steam for 4,000 nautical miles (7,400 km; 4,600 mi) at a speed of 12.5 knots (23.2 km/h; 14.4 mph).
Dupuy de Lôme's main armament consisted of two 45-calibre Canon de 194 mm Modèle 1887 guns that were mounted in single gun turrets, one on each broadside amidships. Her secondary armament comprised six 45-calibre Canon de 164 mm Modèle 1887 guns, three each in single gun turrets at the bow and stern. The three turrets at the stern were all on the upper deck and could interfere with each other. For anti-torpedo boat defence, she carried ten 47-millimetre (1.9 in) and four 37-millimetre (1.5 in) Hotchkiss guns. She was also armed with four 450-millimetre (17.7 in) pivoting torpedo tubes; two mounted on each broadside above water.
The whole side of the ship was protected by 100 millimetres (3.9 in) of steel armour, from the bottom edge of the protective deck 1.38 metres (4 ft 6 in) below the waterline to the edge of the weather deck. The curved protective deck had a total thickness of 30 millimetres (1.2 in) and did not rise above the ship's waterline. Protecting the boiler rooms, engine rooms, and magazines below it was a splinter deck 8 millimetres (0.31 in) thick. The space between the protective and splinter decks could be filled with coal to increase the effective thickness of the ship's armour. It was very cramped there and the coal was very difficult to access. A watertight internal cofferdam, filled with cellulose, ran the length of Dupuy de Lôme from the protective deck to a height of 1 metre (3 ft 3 in) above the waterline. Below the protective deck the ship was divided by 13 watertight transverse bulkheads with three more above the protective deck. The ship's conning tower was protected by 125 mm (4.9 in) and her turrets by 100 mm of armour.
French cruiser Dupuy de Lôme