Thanks Allen. Those are very interesting to us and we can vouch for that #4 book by Holley. We have both volumes, I and II and, if you like reading about big, pre 1898 cannon effects on a variety of armored targets, then you won't be disappointed in those. Both volumes are available as inexpensive, desktop-published, soft covers, rather than rare, expensive, originals.
Very nice, Allen, thanks,
Mike and Tracy