Here is Howe’s union flag:
http://www.nmm.ac.uk/collections/explor ... ID=AAA0730Howe’s flag and the Emerald’s flag have exactly the same incorrect alignment of the St Andrew’s cross that Kester refers to.
However I think the Lord Nelson pub web page is incorrect in saying that the Emerald’s flag was hoisted on the Tower of San Cristobal. It looks as though the museum has two flags, and it was the other that was hoisted on the castle. The Emerald’s flag was taken from one of the boats involved in the landing.
Here are the two flags:
http://www.flickr.com/photos/28220982@N ... 321771879/http://www.flickr.com/photos/28220982@N ... 321771879/See also half way down this page:
http://www.canariascoleccion.com/SECCIO ... LMEIDA.htmI get the impression that the Emerald's flag is very much smaller than the one flown from the castle (which also has a much more regular design). As the Emerald's flag was taken from one of the boats, I wonder whether perhaps it was not the ship's flag, but, similar to Kester's suggestion, one made to be hoisted on the captain's barge, which may be why it has the name on it? This is just a guess, so any other views?