Over there on Rorate a day or two ago was a delightful picture by a Baroque painter of the seventeenth century, Vincenzo Carducci, who worked for the Spanish Crown. It shows the Ordination of S John Matha (and his first Mass in which he received a mercedarian vocation).
Carducci clearly did not accept the then current assumption, based upon the teaching of Pope Eugene IV, that the Porrectio Instrumentorum was the Matter of Ordination. He shows the Holy Spirit descending like a flame of fire upon the head of the Saint as the bishop imposes his hands and says the words Receive the Holy Ghost ...whose sins thou dost forgive, they are forgiven ... etc..
I wonder if the artist and his Most Catholic Royal Patron would have been surprised if they could have known that, four centuries later, Ordination by means of that Matter accompanied by that Form would survive among Anglicans who used the Prayer Book Ordinal (Bishop Harry Carpenter, who had Bossuet on the Dutch side of his episcopal pedigree, dealt thus with me on Trinity Sunday in 1968), but that the imposition of hands with that formula would be abolished in the post-Vatican II Roman version of presbyteral Ordination.
Ah, the whimsies of liturgical history!