Nov 3, 1898, p8
Today, cod liver oil is still used to aid in the treatment of arthritis and multiple sclerosis and one study has even suggested that it may also aid in the treatment of cancer, though this is not to say these diseases can be treated with cod liver oil alone! Cod liver oil is also recommended to be taken during pregnancy as it's believed to reduce the risk of diabetes.
July 30, 1896
Granted, I'm certainly no medical expert but I recently read Germs, Genes, & Civilization: How Epidemics Shaped Who We Are Today which talks a lot about how our resistance to certain infectious diseases grew over centuries and in addition, how infectious diseases were forced to become weaker so that they might spread more easily and survive. Because of both of these natural occurrences, many diseases which were once extremely fatal had a relatively low mortality rate later in history, despite a lack of effective medical treatment. Therefore, it's somewhat understandable how and why people of the past believed in treatments which we now know probably did little to nothing. Over time, it could have been said "since the use of cod liver oil, mortality rates for tuberculosis have dropped by x%" when in reality, they were just seeing a natural decline over time. This is why we still shouldn't jump to conclusions when we see all these statistics about modern medical treatments too - it's difficult to know for sure when we're seeing a direct cause and effect rather than there being other influences at work.
Scott's Emulsion, as seen advertised in these historical newspaper clippings, is actually still in production, although I imagine they no longer market it as a cure for tuberculosis!