because it Swings up to the sand
Swings
It is called a "thurible" or "censer."
Sand, People, Donkeys giving children rides, Swings, Ice-cream stalls, Beach Huts. Small pools, rocks, crabs, seaweed.
They type of timber used in the construction of wooden swings is usually use round poles. Many sets from China use a wood called China Fir. The majority of swings use soft wood as opposed to hard wood.
Something
Strokes.
A beach made of pebbles is often called a "shingle" beach.
Mood swings can be stopped by medicines called 'mood stabilizers'. Examples- lamotrigine, lithium, sodium valproate, carbamazepine.
I don't know the name of it, but it does exist....I have it, too!
An inside pitch
If you mean the time it takes to swing from start to finish (top to top) this is called the period and if it is the number of swings per second this is know as the frequency.