1.  Marriage Record:

2.  1850 Census Images (online at Ancestry.com; Image #214 of 344):  2nd District, Baltimore Co., MD, p. 117A, 1571/1591, enumerated 15 Oct 1850, official enumeration date 1 Jun 1850 (extracted by Diana Gale Matthiesen):

Nathan Corbin	84	M		None		Md
Nathan    "	25	M		Farmer	800	"
Rachel    "	23	F				"
Richard Blakely	19	M		Laborer		"

The senior Nathan CORBIN is our subject's paternal grandfather.  Listed next to the elder Nathan's daughter, Elizabeth (CORBIN) BLAKELY, our subject's aunt.  Richard BLAKELY is said to be Richard Ragan BLAKELY, son of Elizabeth's brother-in-law, Lewis BLAKELY.  Listed two households from Caleb GREENFIELD (æ 48, b. MD), who is two households from Owen BURTON (æ 38, b. MD), who is next to Joseph BURTON (æ 43, b. MD). 

3.  1860 Census Every-Name-Index/Images (online at Ancestry.com):  can't find, and I really looked.  I couldn't find Richard BLAKELY (ca. æ 24), either, which suggests a neighborhood was skipped or a page was lost or a page was not indexed.

4.  1870 Census Every-Name-Index/Images (online at Ancestry.com, Image #56 of 107):  Little Gunpowder P.O., 11th District, Baltimore Co., MD, Roll M593_570, p. 653B, PN 56, 599/400, enumerated 20 Aug 1870, official enumeration date 1 Jun 1870 (extracted by Diana Gale Matthiesen):

Corbin Nathaniel	46	M	W	Farmer			Maryland
______ Rachel	52	F	W	Keeps house			"
______ John	20	M	W	Wks on farm			"
Bean Susan	24	F	W	Domestic			Virgnia

Given that they had no other children, there's some question whether John is their son or a nephew.  Listed next to Richard BLAKELY (æ 37, b. MD, wife Mary).

5.  1880 United States Census and National Index (LDS Family History Resource File: CD-ROM Library):

Census Place: Precinct 1, District 11, Baltimore, Maryland
Source: FHL Film 1254496; NARA Film T9-0496; Pg 406C
	Relation	Sex	Marr	Race	Age	Birthplace	Occupation	Fa	Mo
Nathan CORBIN	Self	M	M	W	57	MD	Farmer	MD	MD
Rachel CORBIN	Wife	F	M	W	63	MD	Keeping House	VA	MD
Olivia BURTON	Niece	F	S	W	17	MD		MD	MD
Charles CULVERTON	Other	M	S	W	16	MD	Farm Laborer	MD	MD
Susan BEANS	Other	F	S	W	36	VA	Domestic Servant	VA	VA

6.  1890 Census:  the 1890 Census Population Schedules were destroyed.

7.  Messages posted to the CORBIN Surname Board (online at RootsWeb.com/Ancestry.com).