I thought this may be of some interest to the cognoscenti?
Western Coast of North America
List of Royal Navy ships on the Pacific Station known to the US Navy May 29, 1862:
1. Bacchante, 51 guns, steam frigate
2. Topaze, 51 guns, steam frigate
3. Termagant, 25 guns, steam frigate
4. Clio, 22 guns, steam corvette
5. Charybdis, 21 guns, steam corvette
6. Cameleon, 17 guns, steam sloop
7. Mutine, 17 guns, steam sloop
8. Hecate, 6 guns, steam sloop
9. Devastation, 6 guns, steam sloop
10. Nereus, 6 guns, storeship
11. Naiad, 6 guns, storeship
12. Grappler, gunboat
13. Forward, gunboat
Some of these ships were sent from India and China in response to the Trent affair. This suggests that there are more ships at Esquimalt as the normal complement there was around 12. There may also be other ships at Valparaiso which is still the main British fleet base in the Pacific until mid-year,
Quotation from Flag-Officer Charles Bell officer commanding USN Pacific Squadron on Lancaster at Mare Island, SF reporting to Gideon Wells Secretary of the USA’s Navy:
“In the present state of the defences of this harbour (San Francisco)
one-half of this force could command the city of San Francisco and take
possession of this yard (Mare Island).”
At this time I have been able to ascertain that the number of guns defending the masonry three tire fort at Fort Point to be 51 many of a smaller calibre. I have been unable to determine how many guns, if any defend Alcatraz nor the number of guns in the smaller emplacement across the bay
List of French warships on the Pacific Station known to the US Navy, May 29, 1862:
1, Le vainqueur Le Dugnay, croisier steamer
2. L’avis Le Cassini, screw
3. La corvette La Bayonnaise
4. La corvette La Galathie
5. La corvette La Cornblie
6. L’avis Le Diarnant, screw
7. Lamothe Piquet, screw
At this time several of these French ships were engaged in blockading
Mexican ports between Guaymas to Acapulco.
Mexican Intervention
Quotation from Captain Powell officer commanding USS Potomac at Vera Cruz, Mexico reporting to Gideon Wells Secretary of the USA’s Navy:
“I had an interview with Commodore Dunlop, who commands the
British forces, ashore as well as afloat. Almost his first words touched
upon the vital point of interest between us. He said that happily the
threatened danger of hostilities had passed away; he was glad to see me
here, “ for,” said he, with the utmost frankness, “when I came down here
I confidently expected that in ten days I should have had my squadron
operating against you on the coast.” This acknowledgment will not
fail to convey to you two weighty facts—first, that the contingent war
orders had been given to the British naval chiefs; secondly, that the
assemblage of the fleet at Vera Cruz, as against Mexico, was only a
cover to the real purpose, to wit, a convenient basis of hostilities
against our line of blockade, the western end of which is only three
days’ sail from Vera Cruz.”
Naval forces at Vera Cruz known to the USN as at 19 Feb. 1862.
British
1. Sans Pareil, screw ship of the line
2. Donegal, screw ship of the line
3. Mersey, screw
4. An unknown of 50 guns
5. Ariadne
6. Challenger
7-16 Some ten others of inferior ratings, all screw ships
By 30 March
Phaeton was sent some ten days previous to the mouth of the Rio Grande.
There remain at Vera Cruz:
1. Mersey, screw
2. Challenger, screw
3. Jason, screw
4. Desperate, screw
5. Barracuda, side-wheel
6-? Some screw gunboats
French
Smaller fleet than the British but still several ships only one identified:
1. Massena, screw ship of the line
By 30 March
Berthollet 6, side-wheel was sent some ten days previous to the mouth of the Rio Grande.
1. An unknown, 100
2. Turenne, 100 but disarmed used as troop ship 1,100 on board
3. Astrea, first class screw frigate
4. Foudre, first class screw frigate
5. Guerriere, first class screw frigate
6-? several smaller vessels.
Spanish
Smaller in numbers and not identified