Hmm seems worse than I originally thought. Everything in bold (with two exceptions) is probably unfit for overseas service.
That'd be surprising in the case of Jasper, which was sold to the Chinese in 1862 and later re-sold to Egypt in 1865.
I don't think you can assume a ship BU 1864 is automatically unserviceable
I can find no record of any of those ships on list being prepared for active service that I have bolded actually undertaking active service before being broken up.
I think that all we can conclude from the 1863-4 breaking up is that the Royal Navy didn't think it was worth keeping these ships on, not that they were necessarily unserviceable. Bear in mind that Gladstone was at the Treasury, there was a cost in both space and money to maintain the gunboat fleet, that the ironclad programme was costing money, that there was the prospect of moving away from the Armstrong gun, and that it was entirely plausible that they didn't need all the gunboats that they had on hand. In particular, the swathe cut through the Second Class Steam Reserve at Chatham and the Haslar gunboat sheds- ships from different builders, which are unlikely to have similar problems in construction- suggests to me that it was a cost-cutting measure rather than a systematic one based on seaworthiness.
That there was no real correlation between the amount of rot and their being broken up is suggested when you look at available information on their state. There are some contemporary observations in the 1860 select committee on gunboats:
Raven: 'in a very satisfactory state', 'small quantity of fungus on the heels of after cant timbers, inside, no decay in consequence'- BU 1864
Redbreast: 'in the same state'- BU 1864
Whiting: 'quite seaworthy'- BU 1881
Fervent: 'small quantity of fungus right aft under the deck, no decay in consequence'- BU 1879 [the Charger, which was in 'much about the same state', was converted in 1866 and sold in 1887]
Prompt: 'fore cant timbers damp and one of them sappy, no decay on consequence'- BU 1864
Earnest: 'In so good a state, compared with some of the others, that we considered it proper to make a remark in her favour' - Sold 1885
Look at the differing fates of the ships which were all observed to 'show a slight degree of dampness at fore and after extremities' at the same time:
Earnest: Sold 1885
Crocus: 'uncoppered, possibly rotten' in 1862, BU 1864
Skylark: 'uncoppered, possibly rotten' in 1862, sold 1906
Wolf: 'uncoppered, possibly rotten' in 1862, BU 1864
Albacore: 'uncoppered' in 1862, BU 1885
Gnat: 'uncoppered' in 1862, BU 1864
Brave: 'a very sound condition, apparently, and the timbers seem very clean and good and dry'; 'commencing planking' 1862, BU 1869
Peacock: 'has a few bad timbers in her'; timbering 1862, BU 1869
Beacon: 'also has a few'; timbering 1862, discarded 1864
Ready: 'a few decayed timbers'; 'planking, good shape' 1862, BU 1864
Thrush: 'a few decayed timbers'; planking 1862, BU 1864
More importantly, Richard Abethell, the master shipwright at Portsmouth Dockyard, was clear that even potentially faulty vessels did have a purpose:
'Do you consider that a gun-boat which is in a very defective state can be considered ready for service?- Yes; she may have many bad timbers in her, and yet be quite seaworthy for home service. If the Caroline had been sent to sea in the state she was, no doubt she would have swum very well, and might have done everything required for home service... there must be a sufficient number of timbers sufficiently sound to hold the planking, and then if the outside planking is good, the ship will hold together very well for duty off the coast.
'Even notwithstanding the concussion caused by the discharge of the guns?- It depends, of course, upon the degree of rottenness, and the number of timbers which are rotten; we should not send a ship like that to a foreign station.'
Rear Admiral Sir Baldwin Walker KCB commented 'there are many vessels now at sea which would otherwise be called unseaworthy. In my opinion these would be fit to go round the world. I have a higher opinion of these gun boats than many have.' He may well have been right: the ships which went on foreign service were sent without any formal inspection, and yet very few of them had to be broken up early. Either there were some exceptionally lucky picks, or the gunboats broken up in 1863-4 were not necessarily unserviceable.
Not necessarily. You've got 18 ships you think are dubious, which (deducting Jasper which was actually fine, Fly at home, and Thistle in reserve) leaves 15 actually required for active service. The gunboats at home can go abroad, and the dubious gunboats can stay in home service. Alternatively, if they're too rotten even for that, there are 6 gunvessels spare in reserve, and 37 gunboats drawn up in the sheds at Haslar in varying states of readiness. And that's assuming that my allocation of 14 gunvessels and 17 gunboats for the American blockade isn't an overstatement.
What do you mean? We have evidence that shows that, OTL, after issuing guns the Union had about 300,000 or so in reserve. Since this involved about a million guns being in Union hands at some point and the Union army was about 500,000 strong at the end of it, the Union's wastage of guns is such that they lost at least 200,000 guns through wastage..
The 300k in storage is on top of the million issued, so technically they lost about half a million guns. However, the point being made was not that the Union could potentially raise another 200k troops, but that they could maintain their deployment levels as of December 1861 and might get 200k guns through the blockade to help them do this. I think the rephrase helps:
we arrive at 538,823 weapons imported/produced between the outbreak of war with the Confederacy and the outbreak of hostilities with Britain in TTL. That means, that the maintenance of the historic troop levels by the Union come January 1861, is plausible by any margin. When given wiggle room for weapons smuggling in the months where the blockade is weakest from March-May 1862 the number of weapons could very well rise to over 700,000[3].
Number of weapons, not number of troops.