As with my two other inventors in this series (X6 and X8) this person was so much more than just an inventor. Unfortunately, if I list all the things he did then this puzzle would become too easy.
Although he originally trained in the same profession as his father, he went on to be a pioneer of a completely different field, within which there were specific methods that he invented. His writings were admired by other great thinkers of the day. OK, so it has to be acknowledged that he had a weird mix of social and political views, some admirable and others very distasteful. Although born elsewhere, in later life he lived and died in a village in Surrey (of course).
There is a blue plaque on a house where he lived outside the county. There is also a memorial to him a long way north of Surrey. Owing to the miracles of modern technology you can read both of these with ease. You need to do this, in order to generate a password.
The password part 1 is from the words on the blue plaque under his dates: (3,2)(4,1)(2,9)
The password part 2 is from the memorial: (7,3,4)(1,3,2)(11,1,5)(2,1,6)(11,6,3)(3,6,1)
For part 3, from his description on the memorial count the number of words between "who" and "born". Convert that number into a letter (A=1, B=2 etc). Combine parts 1 - 3 appropriately into a single string of letters to create the password. Click on the following link, use the password, and then follow the instructions to find out where you must visit en route to finding the cache.
Click link to enter secret password
Please don't leave any spoilers in the logs. Enjoy the hunt! As an inducement, the cache box also provides additional clues to the identity of my previous two inventors (X6 and X8).
For other "X marks" caches in this series click this link