Mustered into service as a Private on July 29th, 1861
Private Lamb was diagnosed with a case of remittent fever soon after arriving in Washington D.C. in the late summer of 1861.
It is possible he was discharged in late 1861 or early 1862. On February 20th, 1862 another Isaac Lamb from Indianapolis enlisted as a unassigned recruit. It is possible it is the same man.
Isaac never filed for a pension.
Unknown date of death or burial location.