OK Jim I'll check but I am sure that they aren't RAW images. Oddly though I checked my gallery just now and all of my attempts have now been uploaded! All of them! So I now have a shed load of images to delete but the problem there is that there are no thumbnails, apart from for one image. Clicking on the "No thumbnail" caption does give me the photo but on deleting one I am taken back to my gallery page, so deleting all of the unnecessary photos is going to take ages!
I'll try uploading again but I won't keep try and see what happens.