Now, anyone can put together a simple arrow weathervane, but the more artistic the vane, the more engineering needs to go into it. To catch the wind properly, the vane’s rear portion needs to have a broader surface than the front, but to swing freely, the (smaller) front must weigh approximately as much as the back. What does this mean, exactly? It means you can’t just throw any old sculpture you like onto a roof and call it a weathervane.
This is Bath Abbey’s west facade. Here angels climb and descend a Jacob’s Ladder to Heaven. There are other symbols on the facade, which all come from Bishop King’s original dream in 1499 when he was inspired to knock down the immense Norman Cathedral and construct on the site of its nave a smaller Tudor Abbey Church.
Apart from the balloon / kite, tabernacle (decorated buttress pinacle) / scaffolding , and Jacob’s Ladder / scaffolding ladder justaposition, look at the shadowed lower left hand corner of the abbey with the carving of the Olive Tree ringed in a crown. Below the top three pagoda tiles and above the crown of the roof pitch, observe that same tree shape!