Art, thanks for your reply. As a matter of fact that particular photo is one of those which does not compare to Philbrick's sketch. The image you refer to is stated to have been included in a claim sent in by gentleman seeking some compensation, if I remember correctly. This would make for interesting reading.
Philbrick's sketch shows the USS ESSEX with rounded sides, but one or two of the photos of the vessel show it with sharp angled sides. Unless there were major repairs or renovations to the vessel, between the time of Philbrick's sketch and the photos being taken, they are obviously different vessels. I may purchase copies of these images for a proper comparison, at a later stage, but I am currently involved in several other projects, so will leave this off for the moment.