(2o6o) 
will do your part in taking care, that fo ufeful and fo neccflary a 
work may not be left undone. 
Lately^ on the QQ/y&.ofy^*'^ (ft.nO about the time of the Sol- 
ftice, I was fearching after the prefent Dediftattonof the AJagntt^ 
which 28 years ago (vid.A. 1642.) I had likewife obferved here 
with great care ^ as about the fame time at Konigsberg Monfieur 
Limumannu^^ihf: then Profeflbr of the Mathematicl<s there.had 
obferved alfo. We both found the xMagnet'ick Needle.at that time 
to decline from the AVr//^ 5 <^ ^\ IVeji rvard. But how it is far o- 
therwife 5 for it declines at prefent, as I have very carefully ob- 
ferved, 7 d, 2o\ to the fame Quarter 5 fo that in the fpace of 
twenty eight years j that declination is increafed 4 d. 1 5 \ ' In the 
year 16285 if 1 remember aright, I found it near 1 degree We^- 
ward: Which declination was affirmed by the Learned Petrus 
Crngerus (once my worthy Prsecepror) to have been 5 about the 
beginning of this Age, or the end of the next foregoing, 8 d, 
Eajl ward'^ the fame Crngerus alfo making ufe of that Oriental 
Declination in defcribing all his Dyals, as may be/een inihe 
Traft he hath written of the fame 5 though it be not certainly 
known by whom, and in what year that Obfervation T.^as 
made. / . 
Further, It appears by our mere recent Obfervatiotis, that this 
Declination of the Load-ftone doth here, Danlzick^^ almoft 
every feventh y ear^ or^to fpeak more precifely^every fix year and 
feven months, increafe to one whole degree , and fo each year, 
to 9'. 6^^. Which is fufficiently confirmed by the Obfervations 
made at Lme-houfe near Lorjdon, by thofe three famous EngJifli 
men, Bnrrowi^Cmter, 2nd Gellibrand : Of whom xhe firji fqund 
the Declination A. 1580. to be f i d, 1 6' y the feco^d ; $ d. !ai6\. 
^o'\ A. 1622 V the ^^/>^,4i. 3^. 30^^ A*i6^4, 
Laftly , It being now certain , that the Needles Declination 
varieth in one and the fame place $ the accurate Obfervations of 
the fubfequent years will (hew , How far this Deflexion will pro- 
ceed, and where, and in what diftance from the true Meridian, 
the very bounds of this Declination realiy are 5 eipeciallyjWhe- 
ther this Libratioti and Variation will be the fame, and regular at 
all times and in all places 5 or whether, and howlongjit will re- 
main Stationary* All which particulars that they may be accu- 
rately difcoveied 5 is a thing very much defired. 'Poffibly confi* 
derable 
