Here is a pdf copy of the 1916 book from the Jesuit missionary Dr. Léon Wieger, discussing Chinese etymology mostly based on the Shuowen (Etymological dictionary from the Han dynasty), but with some critical view of it.

Fascination reading, which debunks some myths. For example, 明 combines 囱 + 月, the moon light through the windows, but no sun! Uncle Hanzi confirms this.
He also proposes that 字, showing a child in the house, originally meant "give birth", because the 字 are complex characters considered as offspring of the 文, simple characters (see p298).

(click on the picture to open the pdf)