[1]: 364 Shortly after his birth, his family moved to Portsmouth, New Hampshire, and in 1816, he attempted to journey west to the new U.S. territories.
The following Spring, they went to Olean Port on the Allegheny River, where they built a flatboat and set off with the entire family and all their worldly possessions.
[1]: 364 At age 16, some of his friends wanted to send him to college to prepare for ministry in the Methodist Episcopal Church, but he refused—his older brother had already left home, and he was the sole support for his mother.
By chance, he encountered a keelboat bound for Galena, Illinois, and came to an agreement with the captain to work aboard the ship during its journey.
[1]: 365 The next year Gardner and his cousin went north into what was then the western portion of the Michigan Territory (now the state of Wisconsin), to work in the lead mines at "Platteville Diggings".
Gardner built a cabin there, about a mile north of the settlement that became the village Platteville, and remained there with his cousin through the Winter of 1827–1828.
[1]: 365 Gardner spent his nights reading by an improvised lamp, made from a lump of lard, a rag, and a button.
His library was limited, but included a Bible, a history of the United States, and a Webster's spelling book.
[1]: 365 Among the miners, Gardner met others who were inclined toward intellectual improvement, and he became one of the founders of a local "debating society".
In the Fall of 1831, having married the woman who would be his wife for the rest of his life, Gardner, despite working long hard hours as a teamster driving his own ox team, was deeply in debt.
By 1835, he had not only paid the debt (with interest), but was able to move his family to Alton, building up a profitable house-building business.
He opened an office in Monroe on December 23, 1842,[2] was admitted to the bar in 1843, and practiced law in Green County for the rest of his life.
[4] In 1861, at the 11th annual Wisconsin State Fair, he served as a judge for "Machinery for the manufacture of sorghum syrup and sugar"; and repeated the duty in 1864.
He seems to have moved into Monroe at about this time, as he was elected as a Village "trustee" (city council member), serving from 1862 to 1864.