166&'] 
Chrifliani Hugenii Ajlrofcofia ccmpendiaria^ Tubi op- 
tici moUmine liberata. Or the defcripthn of an 
Aerial Tehf cope. 
THeufeot Telefiopes, being fo neceffary for it hath 
been the endeavour of fever al lovers of that fcience 
to find out fome more convenient and ealier way, for the 
handling of the fame- Then whereas all the perfcdtibn 
that hitherto hath been added to Telefcopes, chiefly confi- 
fteth, in making them very long and the glaflfes of a big- 
ger fphere, the fame length and bignefs thus increafed, 
hath been ftifled by a troubiefome heavinefs and dif- 
proportion to manage and diredt them to the Stars. The 
Author hence, to take olF c;:^. incumbrance, hath found 
out a devife in cutting or leaving out almolt the whole 
tubcp faving only a fmall part of it near the objective glafs, 
and fomewhat towards the Eye glafs, ordering thefe tv/o 
extremities in luch a manner, that they may do the fame 
fervice, as if the whole tube of one piece fhould be im- 
ployed. To this purpofe he explaiaetli himfelf by afcheme 
and clear defcription, how a maft mufl: firft be perpen- 
dicularly fixed into the ground, which for his own ufe he 
tells, was made of y : foot long, ferving for a ^ elefcope 
of 7 c foot then joyning two parallel rules all along this 
maft, lie declare th how by this means the objective glafs 
may be eafily drawn up and downwards by the help of 
a firing or cord, applied xo an equihbrated weight, fo 
that it be correlpondent to the Eye glafs. The circum- 
ftances whereof can be read in his printed paper , where 
alfo the full ftruiture is to be feen. Only to come to 
the objedion which the Author propofes himfelt, againft 
the ufe of this curtailed Telefcope. The F/r/, is the nckle- 
nefs in keeping alwayes the Eyeglafs in the fame potture : 
to remedy this, he defcribeth a two legged inttrument 
to be put under the 2 arms, to hold them up the more 
fteadily* Secondly^ it feemctli to be a hard matter, to find 
out at night time in fuch a diitance the obje<9:ive glafs 
or the Stars you look for, the cord alone not being able 
to dire6t the whole bufinefs : to help this inconveniency, 
he faith, one maft make ufe of a lantern, which being 
in the fame manner as commonly ufed for the proje£l:i- 
on ofimages> and diperfion of hght, will give direction for 
the finding the objedive glafs, by inlightning the fame for 
to 
