Don Ihde called the hypothesis being 'hyped' and referred to clear evidence about the use of optical tools by, ., Albrecht Dürer and Leonardo da Vinci and others. As well the 1929 Encyclopædia Britannica  contains an extensive article on the camera obscura and cites Leon Battista Alberti as the first documented user of the device as early as 1437.  Ihde states abundant evidence for widespread use of various technical devices at least in the Renaissance and . in Early Netherlandish painting .  Jan van Eyck 's 1434 painting Arnolfini Portrait shows a convex mirror in the centre of the painting. Van Eyck also left his signature above this mirror,  showing the importance of the tool. The painting includes a crown glass window in the upper left side, a rather expensive luxury at the time. Van Eyck was rather fascinated by glass and its qualities, which was as well of high symbolic importance for his contemporaries.  Early optical instruments were comparatively expensive in the Medieval age and the Renaissance. 
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9. Make sure your proposal has a comprehensive review of the literature included. Now this idea, at first thought, may not seem to make sense. I have heard many students tell me that "This is only the proposal. I'll do a complete literature search for the dissertation. I don't want to waste the time now." But, this is the time to do it. The rationale behind the literature review consists of an argument with two lines of analysis: 1) this research is needed, and 2) the methodology I have chosen is most appropriate for the question that is being asked. Now, why would you want to wait? Now is the time to get informed and to learn from others who have preceded you! If you wait until you are writing the dissertation it is too late. You've got to do it some time so you might as well get on with it and do it now. Plus, you will probably want to add to the literature review when you're writing the final dissertation. ( Thanks to a website visitor from Mobile, Alabama who helped to clarify this point. )
It must be admitted that the Pioneer had been a Republican paper before Baum bought it, and perhaps he had to maintain its partisan identification in order to maintain its circulation. Furthermore, Baum's Pioneer , while clearly Republican, was quite progressive: he wrote in support of women's suffrage, alternative religions, occultism, toleration, and so on. So perhaps Baum was a closet Democrat in Aberdeen, forced to hide his true political feelings.