^t(^Cafflm) pretends to evidence by his Obfervations ,' made 
at the fame time at Bonenia, that, the fame day and hour, thofe 
Spots were very large, neer one another , in the midft of the 
Disk, the Oriental bigger than the Occidental (as appears by 
fVg.P, which is that of the fecond Face of Mars.^ 
1 2. Befidcs,he declares^that thofe Aflrommers were too hafty, 
in determining, after f or 6 Obfervations only j in how much 
time Mars finifli's his Revolution^ and denies it to be perform*d 
in 13 hours : adding, that, though Himfelf had obferv'd for a 
much longer time, thaa they ; yet he durft not for a great while 
define, Whether Adars made but me Turn in 24 hours 40 minuts 
or two.y and that allj that he could , for a long time affirm, was 
onelythis, that after 24 h. 40 m* this Planet appear'd in the 
fame manner he did before. 
1 5. But fince thofe firft Obfervations , He affifms to have 
found caufe to determine , that the Period of this Converfion 
is made in the faid fpace of 24 l%40mi and not oftnerthan 
once within that time ; Alledging for proof ; 
1. That, whereas f^^/-.^. (ft.n.) heTaw the Spots of the firft 
V^ctoi Mars, moving from eleven of the Clock in the nighf, 
until break of day^ they appear'd not afterwards in the E- 
vening after the rifing of that Planet(witnefs feveral intelligent 
perfonSjWhich he namcs,that were prefent at the Obfervations) 
Whencebeinfers, that after 12 hours and 20 minuts, thefame 
Spots did not come about j fince that the fame 5 which in the 
morning were fccn in the middle, jipon the rifing of Mars ; after 
13 or 14 hours, might have appear*d neer the Occidental 
Limb. But , becaufe he might be impofcd upon by Vapors, 
whilfl Mars was yet fo neer the Horizon, he gives this other de- 
termination, vU, 
2. Whereas he faw the firft Face of Mars the 6 of February 
at 1 1 of the clock of the night following ; he did not fee the 
fame after 1 8 daies at the fame hour • as he ought to have done, 
if the Period were abfolved in the fpace of 1 2 h» 20 m. 
5. Again, whereas he faw Febr. 24. in the Evening, the other 
Facc-of i^/<ar/, he could not fee the fame, the 13. and ly. day 
of March, to wit after 1 7 and. ip days; as he fhould have done, 
if the Revolution were made in the newly mention'd time. 
4. Again^ whereas the 27. of Marfh in the Evening he faw 
the 
