How do I get my iPhotos from my desktop to my iPad? I tried tapping iPhoto but the merge option does not pop up. only that they have been merged, but my older photos are not there. I need to know ASAP as i have to leave for England tomorrow

Have you tried the Sync option through iTunes?

1) Connect iPad to iMac with USB cable

2) Select your device in iTunes (top left of iTunes window, phone looking icon closest to center)

3) Select Photos from the left sidebar items

4) Check Sync Photos

5) Select iPhotos from sync photos from

6) Choose Sync all photos if you are in a hurry and your library of photos is small

7) Otherwise choose the events or albums you want on iPad.

8) At the bottom right of iTunes click Sync

When I tapped on iPhoto it did not give me the option to merge, that the instructions gave!!

Which instructions are you referring to? There is no "Merge" option, when you sync photo to your iPad.

Which software versions do you have on your iPad and your Mac? Is your profile signature still current (iMac, OS X Mavericks (10.9.4), Desktop)?

If you upgraded to iOS8 and iCloud Photo Library on your iPad, you can no longer sync with iTunes Photo Sync, otherwise uploading with iTunes as described by UGADog is the easiest way.