HEM relatives in Arendal, Telemark? & Denmark

What a wonderful source of information you fine people are! I have a feeling someone will find records to get me back on track with my research. My first query is to find out if Hans HEM, b. 27 Apr 1849 was my grandfather's father OR his grandfather. My grandfather, Lars HEM. was born 28 Oct 1883 in Arendal, I believe. While visiting (now deceased) relatives in Norway over a decade ago, my parents came back with a collection of photographs of Hans Sigurdsen HEM b. 4 Feb 1811 and his wife Johanne Marie Einardatter b. 3 April 1818 and their 10 children: Gudrun HEM b. 15 May 1838 Sigurd HEM b. 22 Sept 1840 Einar HEM b. 17 Feb. 1843 Sveinung H EM b. 22 July 1846 Hans HEM b. 27 Apr 1849 Ingeborg HEM b. 27 Sept 1851 Anne HEM b. 7 Jun 1856 Ole HEM b. 23 Jun 1854 Birgit HEM b. 29 Oct. 1858 Eilif HEM b. 12 Mar 1861 My mother made notes on that visit when this information was acquired that Hans HEM b. 27 Apr 1849 was my father, Sidney Vincent Hem's (1916-2003) GREAT grandfather. However, since Lars was born when that Hans was age 34, and is the youngest of three siblings, I suspect that Hans is actually Lars father... also, we have no other record of Lars' father's name if not that Hans. We do not have Hans HEM's (b. 1849) wife, either. My mother tells me that the HEMS owned a large bakery in Arendal, and that is where all these people came from. In fact, on the 1902 ship manifest where Lars first comes to Brooklyn NY, his occupation is listed as "baker", and origination in Arendal. My second query is about the location of the HEM farm these people came from. I did make a note when talking with my dad in his later years that Hans HEM was Chief of Police and Fire Chief of Telemark district. I have found a geneology line at Ancestry.com that has HEM names back to the 1200-1400's in "Sauherad, TM"... is that Telemark? Can I link my people to this ancient line? My dad years ago had told me our family originally came from Fyn/Funen in Denmark, maybe 400 years ago. I would love to be able to pursue back to this branch if at all possible. Geneology is such a puzzle when I am so far from being able to go and research myself. I appreciate any help. Ellie Hem Hjemmet in the beautiful mountains of east Tennessee, USA