The Jesuit Tomàs Cerdà (1715-1791) gave a famous astronomy course in Barcelona in 1760, at the Royal Chair of Mathematics of the College of Sant Jaume de Cordelles (Imperial and Royal Seminary of Nobles of Cordellas) [REF].
The planet's average speed from n=1 to n=8 decreases moving away the Sun and differs from uniform descent in n=2 to recover from n=7 (orbital resonance).