1a.  Anon.  1966.  Marriage Index:  Ohio, 1789-1850.  Liahona Research, Orem, UT (Broderbund CD-400):

Sly, Henry Clay

McFarland, Margaret

10 Feb 1850

Franklin Co.

1b.  Anon.  1966.  Marriage Index:  Ohio, 1789-1850.  Liahona Research, Orem, UT (Broderbund CD-400):

Sly, Henry C.

Foley, Sarah

22 Nov 1853

Franklin Co.

2.  1850 Census Index/Images (online at Ancestry.com; Image #22 of 26):  Dist. 38, Prairie Twp., Franklin Co., OH, p. 120A/239, 156/157, enumerated 7 Oct 1850, official enumeration date 1 Jun 1850 (extracted by Diana Gale Matthiesen):

Clay Sly	26	M		Farmer	1100	Va
Hannah	17	F				Pa
Susan	68	F				Va
John Hopper	40	M				"

Henry Clay was born in OH (see 1860 and 1870).  His wife is supposed to be Margaret.  Is she Margaret Hannah?  Hannah Margaret?  Susan is Clay's mother, and John is Susan's son from a prior marriage.

3.  1860 Census Images (online at Ancestry.com; Image #33 of 36):  Village of Rome, Prairie Twp., Franklin Co., OH, p. 228A/455, PN 165, 1158/1116, enumerated 3 Aug 1860, official enumeration date 1 Jun 1860 (extracted by Diana Gale Matthiesen):

Henry C Sly	35	M		Merchant	800	300	O
Sarah J	23	F					"
Amanda	9	F					"
James F	5	M					"
Charles	3	M					"
Caroline	6/12	F					"

Amanda is Henry's daughter with a prior wife.  Amanda is also enumerated in her grandmother's household.

4.  1870 Census Index/Images (online at Ancestry.com; Image #10 of 35):  Columbus P.O., Prairie Twp., Franklin Co., OH, p. 732B, PN 10, 72/75, 10 Aug 1870, official enumeration date 1 Jun 1870 (extracted by Diana Gale Matthiesen):

Sly Henry C	48	M	W	Farm Laborer	400	100	Ohio
___ Sarah J	32	F	W	Keeping House			Ohio
___ James F	14	M	W	at School			Ohio
___ Martha J	10	F	W	at School			Ohio
___ Virginia	6	F	W				Ohio
___ Eliza B	1/12	F	W				Ohio