ROOTS
I have begun research on the internet to hopefully find the beginings of our history. There are alot of pay services that will do the work for you but none of what they find out out may  be completely accurate....which is also true for my own "free" research. I have registered into a free user groups area that consists of a bunch of people with the same last name seeking and sharing information.
WHY?
Family tree building and heritage curiosity is as old as we have been on this earth. Many people find a natural desire to quench the question of "where did I come from?" 
HARTMANN:
North German and Danish, a variant of Hart. From a Germanic compound personal name composed of the elements 'hard', 'strong' or 'brave' + man.
The 1920's US census shows that the highest concentration of Hartmann families (approx 350 familes) was in New York state. George Charles Hartmann Jr. was born in Peeksville New York.
It is said that his father George Joseph Hartmann knocked off one of the 'n's sometime in the 1950's. As a busniessman, most of the salesman in that era were Jewish and two n's meant you were a German. This was all less then ten years after the holocaust and WWII, so German and Jewish relationships were very sensative back then.
It is not know if this subtle change in our last name was actually a masquarade used by George Joseph to actually pretend that he was Jewish, but I am going to assume it was.
GILL:
Scottish and Irish. From MacGill then McGill, meaning 'son of a stranger' or from the Irish, MacGiolla 'son of the servant'.
May 2006
In a major breakthrough of roots discovery, Barbara has found out several key elements in our history.
She has been attending a class in Mendham N.J. for the last month or so. It just so happens that it is the same place where our father George C. would take the family for a annual Memorial Day picnic. He would bring is father, George Joseph to the picnic. Mallinckrodt Convent was a place for retired sisters to live. Two of the nuns in the convent were
sisters to George Joseph. Several of the Mighty Ten can remember these picnics and as usual, the older you are, the more you remember.
George Joseph Hartman LEFT
and his first son,
George Charles Hartman RIGHT
Presumably in Westfield, maybe the middle 1950's
Mendham, N.J  (Late 1960's)
Sister Mary Clarella Hartmann (Gertrude) LEFT
Sister Mary Richardis Hartmann RIGHT
with their brother George Joseph LEFT and his son George Charles RIGHT
"Every man is a quotation from his ancestors"
-Ralph Waldo Emerson
Four Letters
Barbara wrote to the current head of the Mallinckrodt Convent inquiring about the sisters. A month later she received four documents. Each sisters letter asking for admission and their "Passing on" letters.
To access two of those letters click HERE. I will be posting the other two letters in THINGS/LETTERS later this month.
UPDATE
I received two emails from ancestory.com pertaining to Charles Hartmann but he middle initial was wrong. I am going to stay in touch with these people just in case. I have also begun digging into the library for books on ancestery research. One of the books I found was Ancestory For Dummies. (perfect!) It is an amazing hobby....but I just don't have the time. So this coluum will update as my investigation slowly unravels. One of my goals is to return to the address in Jersey City mentioned in one of the letters and take a photo of the living establishment there.