
Elijah Cosman, Jeremiah Cosman and Christopher Cosman, sons of John Nelson Cosman of Millstrean New Brunswick, went off to Idaho after 1885. Christopher owned land there but continued on his wandering ways. Elijah lived out his days as a pioneer of Payette County, Idaho and Jeremiah moved on from Idaho to Oregon.
Name: Elijah Dow. Cosman Residence: Payette village, Canyon, Idaho Birth Date: Dec 1860Payette Enterprise
Thursday, July 08, 1915
COSMAN, E. D. "DOW COSMAN" DIES AT ASYLUM
E. D. Cosman, well known to all the old settlers of this community, where he first established his residence more than thirty years ago, died yesterday in the State Asylum at Blackfoot, where he had been a patient for three years. J.B. Cosman, a brother of the deceased, received a telegram at 3:30 in the afternoon, advising him of the death. He wired back to have the body sent to Payette for burial. As the remains will probably not reach this city before this (Thursday) evening, no arrangements have yet been announced for the funeral.
"Dow" Cosman was a pioneer settler of the Payette Valley and for more than twenty-five years had been a familiar figure on the streets of this city, when his mental faculties suddenly became deranged and it became necessary to remove him to the State Institution at Blackfoot, for care and treatment. His brother, Mr. J. B. Cosman, had heard nothing concerning his sickness, and does not yet know the cause of his death. (Riverside Cemetery)
James Blaine Cosman Payette Enterprise
Thursday, September 01, 1910
DEATH ENTERS HOME
The home of Mr. and Mrs. J. B. Cosman was saddened on Tuesday morning August 30th by the sudden death of their three year old son James Blaine, who has been ill but a few days. The little fellow had been ill from but Sunday and was not thought to be in a serious condition but complications developed. Tuesday morning early at six o'clock he passed away. The cause of his death being spinal meningitis. The funeral services were held Wednesday forenoon from the home and interment was made in Riverside cemetery.
James Blaine Cosman was born February 11, 1907, being at the time of his death but a trifle over three years old. He was a bright manly little fellow beloved by all his playmates and the father and mother have the sympathy of many friends in Payette in this hour of sadness. 
Jeremiah B Cosman, 24 October, 1862-6 January 1928, died in Salem Oregon and is buried in lot 345, Salem Pioneer Cemetery. His wife, Mertie, died in California in 1955.

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1920 United States Federal Census about Jeremiah B Cosman
| Name: | Jeremiah B Cosman
| | Home in 1920: | Willow, Payette, Idaho | | Age: | 55 | | Estimated birth year: | abt 1865 | | Birthplace: | Canada | | Relation to Head of House: | Self (Head) [Head] | | Spouse's name: | Mertie born in Missouri in 1878, father born Illinois, mother born, Kentucky | | Father's Birth Place: | Canada | | Mother's Birth Place: | Canada | | Marital Status: | Married | | Race: | White | | Sex: | Male | | Home owned: | Own | | Year of Immigration: | 1883 | | Able to read: | Yes | | Able to Write: | Yes |
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