Egypt and Nubia--from a book published in 1933

In S. G. Seligman's short book, Egypt and Negro Africa, published in 1933, the author takes the position that Egypt had a far range influence on Africa. It's his view that Egypt benefitted Africa, not the other way around.

I found two major contradictions in the work.

On page 18, he gives credit to the Egyptians for the bow and arrow, but even at that time, there was enough evidence to prove the bow was not Egyptian, but Nubian. Before the First Dynasty, Nubian archers joined forces with others and helped unite what is today modern Egypt. These same warriors assisted the new country dynasty after dynasty,

Nubians were celebrated for their skill with the bow and arrow long before Egypt's First Dynasty.

The author contends that Divine Kingship originated in Egypt, but at the end of his book, on page 60, he writes: ""...[C}hronological factors forbid us to believe that the Divine Kings of the Sudan are directly due to Egyptian influence; rather must we regard them as examples of an old and widespread Hamitic belief..."

A number of blogs ago I wrote about how Africans may have brought their culture to the New World--and then, after research and contemplation, realized that the New World could just have easily brought their culture to Africa. After all, the New World pyramids are older than those in Egypt and Nubia.

With that in mind, isn't it possible that Divine Kingship developed in Nubia first (Sudan), spread to Egypt and other places, and eventually took on a life of its own? And can't it also be stated that the Hamites were influenced by the Nubians--not the other way around?