Hi!
There are three John Knotts who are masons in the 1851 Devon census.
Head: KNOTT, John
Name Relationship Mar Age Sex Occupation
Birthplace
John KNOTT Head M 28 M Journeyman Mason
Alphington-Dev
Mary KNOTT Wife M 21 F ---
Alphington-Dev
William H. KNOTT Son - 1 M At Home
Alphington-Dev
Address: Island, St. Thomas
Census Place: Ide St. Thomas, Devonshire
PRO Reference: HO/107/1867 Folio: 294 Page: 27 FHL Film: 0221015
Head: KNOTT, John Neighbors 36847
Name Relationship Mar Age Sex Occupation
Birthplace
John KNOTT Head M 49 M Mason Master No Men South
Brent-DEV
Ellenor KNOTT Wife M 49 F
--- South Brent-DEV
Maria KNOTT Daur U 28 F Laundress
South Brent-DEV
Mary Ann KNOTT Daur U 22 F Laundress
South Brent-DEV
James KNOTT Son U 18 M Mason
St Nicholas-DEV
Ellen KNOTT Daur U 16 F Laundress
Stokeinteignhead-DEV
Lydia KNOTT Daur U 14 F Laundress
Stokeinteignhead-DEV
Elizabeth KNOTT Daur U 11 F Scholar
Stokeinteignhead-DEV
Address: Higher Gabwell, Stokeinteignhead
Census Place: Stokeinteignhead Stokeinteignhead, Devonshire
PRO Reference: HO/107/1872 Folio: 20 Page: 34 FHL Film: 0221020
Head: KNOTT, John
Name Relationship Mar Age Sex Occupation Birthplace
John KNOTT Head M 26 M Mason South
Brent-DEV
Mary Ann KNOTT Wife M 26 F --- Cheriton
Fitzpaine-DEV
Emmily KNOTT Daur - 4 F 1460 Stokeing
Teinghead-DEV
Address: Village, Newton Abbot
Census Place: St Marychurch Newton Abbot, Devonshire
PRO Reference: HO/107/1872 Folio: 116 Page: 11 FHL Film: 0221020
The first of the three would appear to be your man.
I would suggest you obtain your Walter Edward Knott's birth certificate
to confirm that these are his parents, and join the Devon-L Mailing List
(we're a very helpful bunch!)
Best wishes
Sue Hortop
Barnstaple
Devon
Searching for Erasmus/Rasmus in Llanhilleth, Mynyddislwyn, Monmouthshire
and in Merthyr and Llangynidr.
Also Robins, Watkins, in and around Mynyddislwyn.