JF Ptak Science Books Post 1824
Racism and discrimination are never so more obvious I think than when it is present in everyday bit and pieces of our lives, as gratuitous indulgences, unnecessary except to disparage its target--it is at these times that you can see how deeply something is ingrained in the culture of a place.
And an excellent example of this is the transforming/movable puzzle created by the master puzzleteer, Sam Loyd. He patented the idea of mechanism of the thing in 1896 and published it in the same year, selling millions of varieties of the thing. One of the most successful of the puzzles using the design was called, with a fantastically indelicate title, Get Off the Earth.

Working version from the murderousmaths.co.uk website, here.
The title would mean less had not the most popular version of the game featured Chinese men who were getting off the Earth, and this of course at a time of indoctrinated, inculcated, adjudicated and legislated, legalized segregation and discrimination. It was a time of very high Sinophobia, with all manner of advancements against people of Chinese descent: the Anti-Coolie Laws of 1862, the Pigtail Ordinances (of California) of 1873, the Chinese Exclusion Act of 1882 (renewed in 1892 and 1902), and so on, displayed America's unease and at times hatred of the Chinese people. Loyd referred to the men as "warriors", which I think disingenuous, as the characters hardly have a warrior-like quality to them--they are simply racist. And they were being made to disappear from the Earth, something many people in this country wanted to happen.
According to several web sources, the puzzle was actually used by the William McKinley campaign of 1896 in an effort to out anti-Chinese his opponents2.
What these objects do for us today is help us think about what "get off the Earth" objects we have in 2012, and how awful they'll look in the decades to come. The fabric of society has not crumbled under the weight of allowing non-land-holders to vote, or to allow women more equal rights or the right to vote; abandoning slavery did not crush the country, nor did Brown v. Board of Ed, nor did the abandonment of the miscegenation laws. I can hardly believe that an issue such as Gay marriage will be the great under of the Republic as it has been present in legislation and state constitutional amendments; it will look as bad in a few decades from now as does the Get off the Earth puzzle looks now, or the idea of slavery, or the idea of voting privileges only for the privileged male, or maintaining Jim Crow laws, and so on, on a nd on into the misty night of bad ideas and societal discrimination.

Notes:
1. Nice stories on Sam Loyd and deep on puzzles in general, here. Sam Loyd's book of 5,000 puzzles.
2. A summary of the McKinley presidential campaign making use of the puzzle to help raise itself in the eyes of the anti-Chinese voters, see here.
The odd thing is that current sites have referred to the men surrounding the globe (below) as "Chinamen", or still use the Loyd reference to "Chinese warriors", and many still hold to the indulgences that this is a simple puzzle and nothing else. It is hardly that simple.