Thanks for effort you've put into the research, Cedars. Its useful to have that as a resource.
The greatest value that I can see in this though, is that it demonstrates that the "thinking" of the Bible students/Jehovah's Witnesses is the "thinking" of humans, as indeed is ALL religious thought on this earth, since there seem to be no divinities in the universe who pass on logical, rational ideas to humans.
I would like to point out that the racist ideas you've highlighted in the WT literature, merely expresses common attitudes in the 19th and a good part of the 20th centuries. Attitudes that were based on imagining a world controlled by Europeans and that needed to rationalise that situation.
The basis for these racist attitudes has been analysed by academic John M. Hobson (the great-grandson of J.A.Hobson) in his book The Eastern Origins of Western Civilisation. (Cambridge University Press, 2009). Hobson argues (Ch 10) that European (including the USA) Imperialism attempted to explain and justify their dominance of the world. Europeans (whites) by their success, could be glorified as "the lords of mankind." Their imperial ambitions would be spread through their military superiority, through capitalism to control economies, and through science to provide a new knowledge for all, and through politicians to spread the message of democracy (albeit limited at first), and used the missionising of the world by churches to provide an alternative (superior in their eyes) philosophical basis for western dominance.
Using the new ideas of Social Darwinism and "scientific racism," and as the leading European power, the British particularly incorporated racist ideas into their thinking and graded the world as they saw it, into categories.
At the top, in the Premier Category, dominating all, were the Anglo-Saxon British.
Category 1: Europeans, with the Germans at the top, followed by the Catholic French and so on, to the Catholic Portuguese at the bottom. The Catholic Irish were abitrarily excluded from this category and located in category 3. In the eyes of the British, the Irish were the 'missing link' between the gorilla and the negroes. Whether or not that was meant to be satirical is beside the point. It illustrates how race was being used to imagine the world as dominated by the Anglo-saxon British. Hobson provides quite a range of writers from the era who spout this concept of the world.
Category 2, consisted of essentially Asian " yellow/barbaric" peoples.
Category 3, races (mostly black- but including the Irish) were gauged as barely human. A typical attitude may be seen in Edward Long's claim, "I do not think that an orang-outang husband would be any dishonour to a Hottentot female." ( History of Jamaica).
Surrounded by this pseudo-scientific thinking, it is little wonder that the Russel and Rutherford fell victim to the idiocy of these ideas.
Even as late as the end of the 19th C, we have Rudyard Kipling writing, The White Man's Burden, in support of Theodore Roosevelt' invasion of the Phillipines and the very nasty war waged by the US, against Phillipino Independence fighters.
If you have not read Kiplings excursion into racism, you can easily google a copy. Kipling describes Phillipino's as "half devil and half child." And writes of whites sacrificing their best young men to subjugate and then educate Asians and Blacks*
Of course, it was not only the predeccessors of the JWs that held to these racist notions, many other religions accepted these ideas. After all, Western Imperialism opened the path for their missionary efforts.
"thank you Jesus for opening the way."
* Imagine the shock then, when the Japanese defeated the Russians in their 1905 war. Yellow men defeating whites. Shocking!!