I remember reading a great answer [1] from Stack Exchange, that claims: > the 1873 treatise used a pre-Heavisde form of vector calculus cannnibalized from Hami

I remember reading a great answer [1] from Stack Exchange, that claims: > the 1873 treatise used a pre-Heavisde form of vector calculus cannnibalized from Hamilton's quaternions ... only sparingly, to present the equations in capsule summary form. Thanks for the reply. From your link, I now understand what does "vector calculus cannnibalized from Hamilton's quaternions ... only sparingly" means. [1] https://hsm.stackexchange.com/a/15618 https://hsm.stackexchange.com/a/15618