Volume
The volume of J35 can be calculated as follows:
J35 consists of 2 cupolae and hexagonal prism.
The two cupolae makes 1 cuboctahedron = 8 tetrahedra + 6 half-octahedra. 1 octahedron = 4 tetrahedra, so total we have 20 tetrahedra.
What is the volume of a tetrahedron? Construct a tetrahedron having vertices in common with alternate vertices of a cube (of side, if tetrahedron has unit edges). The 4 triangular pyramids left if the tetrahedron is removed from the cube form half an octahedron = 2 tetrahedra. So
The hexagonal prism is more straightforward. The hexagon has area, so
Finally

numerical value:
Read more about this topic: Elongated Triangular Orthobicupola
Famous quotes containing the word volume:
“Love is both Creators and Saviours gospel to mankind; a volume bound in rose-leaves, clasped with violets, and by the beaks of humming-birds printed with peach-juice on the leaves of lilies.”
—Herman Melville (18191891)
“We are too civil to books. For a few golden sentences we will turn over and actually read a volume of four or five hundred pages.”
—Ralph Waldo Emerson (18031882)
“I dare say I am compelled, unconsciously compelled, now to write volume after volume, as in past years I was compelled to go to sea, voyage after voyage. Leaves must follow upon each other as leagues used to follow in the days gone by, on and on to the appointed end, which, being Truth itself, is Oneone for all men and for all occupations.”
—Joseph Conrad (18571924)