2. In the classical languages the partitive power was expressed by the genitive.
"The English Language"
Robert Gordon Latham
The construction is a construction that has grown out of the partitive power of the genitive case; for which case the preposition of, followed by the objective, serves as an equivalent.
"The English Language"
Robert Gordon Latham
61.3: This war lasted from 192 to 190. 61.4: partitive gen.
"Selections from Viri Romae"
Charles François L'Homond