The book title of book titles

MacDonell's A Sanskrit Grammar for Students (Oxford, 1927: xiv) refers to a work called gaṇa-ratna-maho-dadhi 'the ocean of the gems of word-groups' by Vardhamāna in 1140.





This title surely puts the Thesaurus Linguae Latinae or Linguae Graecae to shame and in the shade.
  In relation to ratna, recall, from the first stanza of the first Vedic hymn to Agni (RV 1.1), ratna-dhā_tama(m) 'best bestower of ratna ('treasure')'. There are no IE cognates for ratna.