Square windows on a plane! Never knew that :)
Cylindrical tankers have no weak spots that may require reinforcement
Now, it seems SO obvious 😅.
I like very much the way you manage to pack a lot of interesting info in a concise way @greenrun. I must learn that from you 😊.
Lots of love to you Green :)
Thank you for the compliment. We all learn from each other :)
That is the beauty of steemit.