It is said that Isaac died in Cincinnati, OH, but he is in the 1860 and 1870 censuses of Kenton Co., KY, and his widow is in the 1880 census of Kenton Co., KY, so it seems more likely he died in Kenton Co.  In the bio of their son, Walter Ferry STRAUB, it is said his parents were living in KY, just south of Cincinnati (i.e., Kenton Co., KY) in 1876.

— born in Lewistown, Mifflin Co., PA:
  8.  Frances C. STRAUB, b. 1836

— born in PA or OH:
  9.  (Son C) STRAUB, b. 1835-40

— born in Cincinnati, Hamilton Co., OH:
10.  Elizabeth STRAUB, b. 1838; living in 1880; m. Mr. HOPPER; had daughter, Catherine HOPPER, b. 1869/70, OH
11.  Emma STRAUB, b. 1844
12.  George M. STRAUB, b. 1847/8; living in 1880; unmarried as of 1880

1.  Marriage Records:

2.  1830 Census Index and Digital Images (online at Ancestry.com; Image #5 of 16; extracted by Diana Gale Matthiesen):¤•

1830

PA

Northumberland Co.

Borough of Milton

p. 139

Ln. 25

Isaac Straub

200 001 - 201 110

These data indicate:

No. & Sex	Age Class	Therefore Born	Individuals Inferred
2 males	4 or under	1825-1830	= Son B = Son A
1 male	30-39	1790-1800	= Isaac (b. 1794)
2 female	4 or under	1825-1830	= Daughter A = Mary Caroline (b. 1824/5)
1 female	10-14	1815-1820	= ?
1 female	15-19	1810-1815	= ?
1 female	20-29	1800-1810	= Elisabeth? (b. 1799) or Ann? (b. 1807/8)

Isaac is old enough to be the father of the two older girls from a prior marriage, but Isaac was not head-of-household in the 1820 census, so I doubt they are his daughters.  Isaac was afluent, so he certainly could have afforded hired help for his wife.

3.  1840 Census Index and Digital Images (online at Ancestry.com; Image #53 of 62 — indexed "Isaace Straub"; the numerical data pages precede the name pages; extracted by Diana Gale Matthiesen):¤•

1840

OH

Hamilton Co.

Cincinnati (Ward 6)

p. 264B

Ln. 23

Isaac Straub

100 200 100 - 222 001 000

0002000

These data indicate:

No. & Sex	Age Class	Therefore Born	Individuals Inferred
1 male	4 or under	1835-1840	= Walter (b. 1834)
2 males	15-19	1820-1825	= Son B = Son A
1 male	40-49	1790-1800	= Isaac (b. 1794)
2 females	4 or under	1835-1840	= Elizabeth (b. 1838) = Frances (b. 1836)
2 females	5-9	1830-1835	= Daughter C = Daughter B
2 females	10-14	1825-1830	= Daughter A = Mary Caroline (b. 1824/5)
1 female	30-39	1800-1810	= Anna (b. 1807/8)

The sons are in the wrong age classes, yet I don't doubt these are our subjects.

4.  1850 Census Images (online at Ancestry.com; Image #162 of 262 — indexed "Isaac Straule"):  Cincinnati (Ward 4), Hamilton Co., OH, p. 353A/705A, 669/1116, enumerated 15 Aug 1860 (extracted by Diana Gale Matthiesen):¤•

Isaac Straub	54	M	Machineist		Penn
Ann       "	41	F			"
Walton    "	16	M	Clerk		"
Frances C "	14	F			"
Elizh     "	12	F			O
Emma      "	6	F			"
Geo       "	2	M			"

5.  1860 Census Images (online at Ancestry.com; Image #69 of 628 — indexed "Isaac Straule"):  Florence P.O., District No. 1, Kenton Co., KY, p. 353, PN 69, 514/572, enumerated 14 Jun 1860 (extracted by Diana Gale Matthiesen):¤•

Isaac Straub	64	M		Mill Wright	25,000	10,000	Pennsylvania
Anna      "	52	F					"
Walter    "	25	M		Lawyer			"
Frances   "	23	F					"
Elizabeth "	21	F					Ohio
Emma      "	15	F					"
George    "	10	M					"
Martin Doughty	37	M		Farm Hand			Ireland
Mary Reed	21	F		Domestic			"

6.  1870 Census Images (online at Ancestry.com; Image #35 of 50):  Covington P.O., Scott Pct., Kenton Co., KY, p. 307A, PN 35, 240/237, enumerated 17 Sep 1870 (extracted by Diana Gale Matthiesen):¤•

Straub Isaac	75	M	W	Retired Merchant	25,000	52,375	Pennsylvania
______ Ann	63	F	W	Keeps House			Pennsylvania
______ Emma	26	F	W	At Home			Ohio
Jones Fountain	22	M	B	Farm Laborer			Virginia
_____ S???	23	F	B	Domestic Svt			Kentucky
_____ John	2	M	B				Ky

7.  1880 Census (indexed at FamilySearch.org; page image online at Ancestry.com, Image #28 of 48):  Scotts Magisterial District, Kenton Co., KY, Roll T9-0426, p. 609D, PN 28, SD 4, ED 127, enumerated 17 Jun 1880, official enumeration date 1 Jun 1880 (extracted by Diana Gale Matthiesen):¤•

1880:  for an explanation of the column headings, please see What the Numbers in the Federal Census Mean (missing columns contained no data).

1

2

3

4

5

6

8

9

10

11

13

24

25

26

236

241

Straub Ann

W

F

71

/

Keeping House

Penn

Ireland

Ireland

______ F Walter

W

M

43

Son

/

At home

"

Penn

Penn

______ M George

W

M

31

Son

/

Farmer

Ohio

"

"

Hopper Elizabeth

W

F

39

Dau

/

At home

"

"

"

______ Catharine

W

F

10

G-Dau

/

"

"

England

Ohio

Butler Frances

W

F

80

Sister

/

Penn

Ireland

Ireland

Eucher Oreich

W

M

38

Domestic

/

Domestic

Switzerland

Switzerland

Switzerland

Tone Alice

W

F

15

"

/

"

Kentucky

Ky

Ky

Johnson Blanche

B

F

50

"

/

Kentucky

"

"

8.  Anon.  1911.  Genealogical & Biographical Annals of Northumberland County.  J.L. Floyd & Co., Chicago. Biographical sketches of Jacob Straub and his kin. 

9.  William Henry Egle.  1898.  Notes and Queries: Historical, Biographical and Genealogical: Relating Chiefly to Interior Pennsylvania: Annual Volume, 1897.  Harrisburg Publ. Co. Harriburg, PA (reprinted 1970 Genealogical Publ. Co., Baltimore, MD; republished 1998 as Broderbund CD-19.  Biographical sketch of Isaac's father, Andrew Straub, Founder of Milton, on pp. 41-42. 

10.  Herbert C. Bell.  1891.  History of Northumberland County.  Brown, Runk, & Co. , Chicago.

TURBUT TOWNSHIP... MILLS. . . In 1840 Abraham and Isaac Straub removed their extensive grain and lumber mills from the island opposite Milton to the mouth of Muddy run. They were the inventors of a reaction water-wheel, the first in the United States, and their operations were quite extensive. Their water power was derived from the river, dams having been constructed on both sides of the island; but the erection of the Lewisburg dam interfered with these arrangements, and hence the selection of a new location at the mouth of Muddy run.  Chamberlain & Bisel, Yager & Bisel, John Ott, and W.B. Kemerer successively continued the business; on the 28th of March, 1874, the mill was burned, involving a loss of twenty thousand dollars. It was immediately replaced by the present building, a substantial frame structure.

11.  Information found by Frank Stroup at the Pennsylvania Historical Society in two folders of unpublished notes entitled Helen Gearhart Collection.  These notes were entirely undocumented, so caveat emptor; yet to the degree that these notes are correct, they contain much valuable information, so are worth consulting.  See Archives of the STRAUB-L mailing list (online at RootsWeb.com; and search on "Gearhart"). 

12.  Charles Robson, ed.  1876.  The Biographical Encyclopaedia of Ohio of the Nineteenth Century.  Galaxy Publ. Co., Cincinnati, OH (online at the Making of America web site).   On p. 40 is a biographical sketch of our subjects' son, Judge Walter Ferry STRAUB.  It states, among other things, that in 1876, Isaac and Anne were living in Kentucky, just over the state line from Cincinnati, OH (which would be in Kenton Co.). 

13.  Anon.  Monday, 18 Jan 1886.  "Condensed News: Topics of the Times Cut Short for Hasty Readers."  The Marion Daily Star (Marion, OH). Vol. IX, No. 65, p. 1 (online at Ancestry.com):

Miss (sic) Annie STRAUB, mother of Judge Straub, died in Kenton county, Ky., aged seventy-nine years.  Her husband, Isaac Straub, died in 1875.

14.  Contributors:  Jim Burnell, Frank Stroup.