Pascal's Law Apparatus Equilibrium Tubes Vases Vintage Science Cast Iron.
Please see the pictures for the best description. These do not sit perfectly in their spots. I assume you would use wax or something to give them a good seating, so keep in mind some of these are sort of loose. The one with the double ball on the end is just resting in there and has no seal as it is way too small for the opening. It appears that this has standard size openings that you would put a sizer in for the size of tube you are using. The tubes look pretty good, but there is some chipping along the bottom of some of them. It is in very good shape, and will be packed incredibly well. Shipping cost will reflect the packing job as this will be Double or triple boxed.