Just as a cautionary tale have a look at this thread - it's not pleasant but shows the risks.
http://www.tortoiseforum.org/threads/help-3-4-mo-old-attacked-by-cat.118042/
There are others about cats scratching torts eyes and dog attacks too so do a search in Tortoise Health
http://www.tortoiseforum.org/threads/help-3-4-mo-old-attacked-by-cat.118042/
There are others about cats scratching torts eyes and dog attacks too so do a search in Tortoise Health