This 165-page "monograph, based on lectures delivered to the postgraduate class at the Johns Hopkins Hospital in 1893, includes 67 case reports and 43 illustrations, some of which are photographs that depict patients or autopsy findings. Osler delivered separate lectures on tumors of the stomach, liver, gall bladder, intestines, and kidney. Harvey Cushing explained that these 'carefully prepared lectures on 'The Diagnosis of Abdominal Tumors', [were] subsequently collected and published (1895) in book form....It was evidently his intent to compare, so far as possible, the provisional clinical diagnoses of the cases with the subsequent findings at autopsy or at operation.' Cushing 1:391. It is important to appreciate that Osler's monograph was published before the discovery of X-rays. Maude Abbott claimed, 'These lectures are based on post‑mortem findings with histological studies of the specimens, and thus will always have a permanent value for the clinico‑pathologist.' Abbott (1939) 65." (W. Bruce Fye). 

Digital facsimile from U.S. National Library of Medicine at this link.