The memorandum shows that Nelson originally contemplated a formation in three lines, an advanced division to windward, a main division under his personal command, and a lee division under his second-in-command, Collingwood. The final grouping of the ships in the battle was in two divisions. In the following list of the British fleet the names of ships are arranged in the same order in which they appear in Collingwood's dispatch, written after the action:—

Windward Line.
Ships.Guns. Commanders.
Victory100 Vice-Admiral Lord Nelson.
Captain Hardy.
Téméraire098 Cap"ain Harvey.
Neptune098 Cap"ain Fremantle.
Leviathan074 Cap"ain Bayntun.
Conqueror074 Cap"ain Pellew.
Britannia100 Rear-Admiral Lord Northesk.
Captain Bullen.
Agamemnon064 Cap"ain Sir E. Berry.
Ajax064 Lieutenant Pilfold.
Orion074 Captain Codrington.
Minotaur074 Cap"ain Mansfield.
Spartiate074 Cap"ain Sir F. Laforey.
Africa064 Cap"ain Digby.
Leeward Line.
Ships.Guns. Commanders.
Royal Sovereign0100 Vice-Admiral Collingwood.
Captain Rotherham.
Belleisle074 Cap"ain Hargood.
Mars074 Cap"ain Duff.
Tonnant080 Cap"ain Tyler.
Bellerophon074 Cap"ain Cooke.
Colossus074 Cap"ain Morris.
Achille074 Cap"ain King.
Dreadnought098 Cap"ain Conn.
Polyphemus064 Cap"ain Redmill.
Revenge074 Cap"ain Moorsom.
Swiftsure074 Cap"ain Rutherford.
Defiance074 Cap"ain Durham.
Thunderer074 Lieutenant Stockham.
Defence074 Captain Hope.
Prince098 Cap"ain Grindall.
Besides one frigate of 38 guns, three of 36, and two brigs of 12 and 8 guns.

This was the fleet that lay off Cape Sta. Maria, some fifty miles from Cadiz, on Saturday, 19 October, 1805, and received from the frigates watching the port the message, passed on by connecting ships, that the enemy was at last coming out.

Villeneuve, like Nelson, had originally divided his fleet into three divisions. On the day of battle it fought in an order which was (as we shall see) partly the result of chance, arrayed in a long double line. He had deliberately mixed together in his array the French and Spanish units of his fleet, to avoid the dangers that might arise from mutual jealousies if they were drawn up in divisions apart. Instead of giving the list of his fleet according to the ordre de bataille drawn up in Cadiz harbour long before the event, it will be more convenient to arrange the list as they actually lay in line from van to rear on the day of battle.

The following, then, is the list of the allied Franco-Spanish fleet:

Ships.Guns. Commanders.
*Neptuno080
Scipion074 Captain Bellanger.
Intrépide074 Commodore Infernet.
Formidable080 Rear-Admiral Dumanoir le Pelley.
Captain Letellier.
*Rayo100 Commodore Macdonel.
Duguay-Trouin074 Captain Touffet.
Mont Blanc074 Commodore La Villegris.
*San Francisco de Asis074 Captain de Flores.
*San Agustino074 Cap"ain Cagigal.
Héros074 Cap"ain Poulain.
*Santisima Trinidad130 Rear-Admiral Cisneros.
Commodore de Uriarte.
Bucentaure080 Vice-Admiral Villeneuve.
Captain Magendie.
Neptune080 Commodore Maistral.
Redoutable074 Captain Lucas.
*San Leandro064 Cap"ain Quevedo.
*San Justo074 Cap"ain Gaston.
Indomptable080 Commodore Hubert.
*Santa Ana112 Vice-Admiral de Alava.
Fougueux074 Captain Baudouin.
*Monarca074 Cap"ain Argumosa.
Pluton074 Commodore Cosmao Kerjulien.
Algéciras074 Rear-Admiral Magon.
Captain Letourneur.
* †Bahama074 Commodore Galiano.
Aigle074 Captain Gourrège.
† ‡Swiftsure074 Cap"ain Villemadrin.
Argonaute074 Cap"ain Epron.
* †Montanez074 Cap"ain Alcedo.
* †Argonauta080 Cap"ain Pareja.
Berwick074 Commodore Filhol-Camas.
San Juan Nepomuceno074 Comm"dore de Churucca.
Ildefonso074 Comm"dore de Vargas.
Achille074 Captain Deniéport.
Principe de Asturias112 Admiral Gravina.
Rear-Admiral Escaño.
Besides five 40-gun frigates and two corvettes, one of 18, the other of 16 guns.
*Names of Spanish ships are distinguished by being marked with an asterisk.
Ships of the "Squadron of Observation" originally intended to act independently under Gravina.
Formerly British.

So far as mere figures can show it, the relative strength of the opposing fleets may be thus compared:—

Line of Battle.Lighter Ships.
Ships.Guns.Frigates.Guns.Brigs and
corvettes.
Guns.
British fleet2721484146220
Allied fleet3326265200230

But here once more—as so often happens in naval war—the mere reckoning up of ships and guns does not give the true measure of fighting power. The British fleet was immeasurably superior in real efficiency, and the French and Spanish leaders knew this perfectly well.