Ranger was intended to be a flush-deck design, the island being added after construction began, hence the folding funnels to clear the deck for flight operations. Akagi and Kaga had two different funnel arrangements prior to their reconstruction in the late 1930's. Akagi had one funnel pointing out and down, while the other pointed up. Kaga had her funnels trunked along the sides of the hull to the stern, where they discharged down and aft. All the Japanese carriers with side funnels had shields on the guns aft of the funnel on that side to protect them from gasses. The sideways funnels must not have been too bad, since the late war Amagis were virtual copies of the Hiryu and they must have amassed some experience by then with the two different styles.