[ P5 ] 
of Months might be engraved upon Tome other Me- 
ridian. It would be of Ufe like wife, if the Parallels 
and Meridians of every Degree between the Tro- 
pics be drawn in faint Lines, which I think might 
be done without obfcuring the Map. 
Parallel to the Horizon, and 1 8 Degrees below it, 
I had a Circle fixed for fhewing the Limits of the 
Twilights: This is ufeful, as it ftiews at one View 
the State of the Twilights, and alfo why they do not 
lengthen or fhorten, as the Days do. The Semi- 
circle of Pofition is a thin narrow Plate of Brals as 
ufual, but made fo that its Axis is moveable quite 
round the Horizon. 1 had alfo a narrow flexible 
Slip of Brafs, which might be girt round the Globe 
in any Pofition, and fo be made to reprefent any 
great Circle whatfoever : This occafional Circle 
may be inftrudtive to Beginners on feveral Oc- 
cafions. 
If the principal Horizon be of Wood, or made fo 
as to obfeure the Globe below it, the Twilight Ho- 
rizon had beft have fmall Feet of a proper Length 
fixed fo that it might ftand in its proper Place upon 
the other, occafionally ; then inverting the Pofition 
of the Globe, the fame thing will be fliewed as 
before. 
The farther Ufe and Application of thefe Contri- 
vances to different Projedions of the Sphere, 
will be obvious to thofe who are acquainted with 
thefe things j and without dwelling any longer upon 
this Sub) eft, it may feem, that I have already faid 
more than was needful in this Place. But the Globe 
being in every-body’s Hands, and in reality a very 
ufeful, entertaining and inftruftive Inftrumentj I 
T t 2 thought 
