' < rt« ) 
tlons, by me mz&t ttetcon during that tmt • the other, Tome 
years after the fbtmer : Both which I thought fit to coftitnuni-^ 
cate to you, to dirpofeof thera as you lhall think good. 
So far the Letter : Which, together with the Invention and 
Contrivance it felf, therein mentioned, the Publiflier would 
have given notice of ere this, and at the time, when in 1 2 7. 
of thefe Trafts the \\kt Invention, imparted from Duhlhy was 
defcribed , if he had not then been altogether Un-acquainted 
therewith. Wherefore, to do right to the Ingenuky of this In- 
ventor, the Defcription of this his Inftrument, in' its two fe- 
vera! contrivances, fliall now be faithfully fetdown here, toge- 
ther with the Obfervations made by thefprmcr of them. 
the Explamtmof thefitjl Contrivmcein Figure I. 
AAAA, The Frame of wood for the two pannels of Deal to ' 
play loofe in at top and bottom, to which ac the two ends they 
are faftned^ ' ' \ ' 
BB, The two pannels of flic-Deal, three foot deep,and three 
foot broad apiece , with a diftance left in the middle for t|ie 
fcopeof themotion. 
C, The Hand placed or faftened by the Axletree to the plate, 
and aifo withNail-hoIeS which are to faften it to the middle of the 
Pannel within half an inch of the fcope for motion; at the lower 
or fliorter end of which Axletree there is, by a wire liiie an S, 
faftneda finall Silver-chain within a ft rav\s breadth of the Axle- 
tree; which Chain is to be carried and placed crofs the diftance 
between the two pannels, and faftncd to ibe^^annel oppoGte by 
a brafs noofe, through which it is to flip , fo as that it may be 
taken up or let down at pleafure. 
D, TheRoller with a weight annexed, which by a firing is 
Faftned to the loweft end of the hand C ; fo that as tlie Relax 
gives way,the Weight will adjuft the motion of the band tc^ the 
Index E. 
E, Thelndexof Paper, patted upon the oppofite pannel 
to the hand^and fo, as it is in this figure,placed near the top, for 
the better advantage of the Hands motion ; and this Index,be- 
ing but a quarter of a Circle, is divided into inches more or 
fewer according to the fcope which ihei Pannels hand requires 
for their motion ; but when the Relax lhall require more room 
for the hand, then thechain is to be taken up one link more,and 
fo 
