Croatia 1943 – Ruder Boskovic

Ruder (or Rudjer) Josip Boskovic (1711–87) was a Croatian mathematician, astronomer and physicist. He was born in Dubrovnik but spent most of his working life in Italy; as a result he is also known by his Italianized name of Ruggero Giuseppe Boscovich. He studied light and optics and recommended the use of compound optics for overcoming chromatic aberration in refractors. This stamp shows him using a small telescope and clasping what may be intended to be a globe of the Earth, as geodesy was another of his interests. In the 1760s he helped found the Jesuit observatory at Brera, near Milan. Boskovic devised the first method of computing an object’s orbit from just three observations. He was also a pioneer of the theory of atomic forces.

The 73rd stamp in each sheet of 100 contains a small addition: a letter “S” on Boskovic’s right hand, being the intial of the stamp’s engraver, Karl Seizinger (see detail at left).

SG number
Face value
3.50 k
Dark red
12.50 k
Dark brown