In 1874, Isaac Vail, put forth the water canopy idea. https://www.creationscience.com/onlinebook/FAQ32.html Though you will find it hard to find this in the old WTS publications, the WTS based the water canopy idea on this man's ideas. But the WTS has kept the water canopy idea without contributing it to Vail.http://www.talkorigins.org/faqs/canopy.html
https://www.jehovahs-witness.com/topic/152570/whence-flood-waters-flood-water-canopy-theory
The Witnesses' J. F. Rutherford promoted the Canopy Theory in his 1927 book Creation. [13] "Jehovah God," said Rutherford, commenced an "increase of light upon his great work for the benefit of man about the year 1874 A.D."--referring to publication of Vail's pamphlet. Rutherford presented Vail's theory in the context of the Witnesses' 7,000-year-long Day/Ages of Creation. According to the Witnesses' popular book Did Man Get Here By Evolution Or By Creation?, [14] the Bible explains that "a vast water canopy was suspended high above the Earth, and its fall caused a global deluge in the days of the man Noah, who wrote an eyewitness account of the event." The Canopy shielded the Earth from cosmic rays, reducing the formation of carbon-14, thus making radiocarbon-dated antediluvian objects appear older than they really are.