< on with it. By this means, the variation may be had well enough 
to degrees, half degrees, and Tome fmaller parts 5 and if carefully 
and curioufly profeeuted, even to Minutes too. But it will not be 
amifs, to do it both by the Sun and Stars, that the greater certain- 
ty may be attained, 
2. To carry T>ipping~S\(ecclles with them, 
nr 1 He Dipping-Needle is to be ufed at leaft as frequently as the 
A former Experiment is made, and in the fame places, in or- 
der to the fame purpofes. All that needs be faid of the Manner, 
is, that when the Dipping of the Needle is to be examined , the 
Circle, in which it moves, is to be hung perpendicular, and turned, 
till it be juft in the Magnetic^ Meridian^ where it dippeth moft, 
and the degree of its depreffion under the Horizon is to be noted in 
a 7 Able. See Figure i e 
3. To marine are fully the Flowings and Ebbings 
of the Sea, in as many f laces as may he. 
He Particulars here to be regarded, are, i. The precife times 
of the beginnings of the Flood and Ebb, in allditeis, Bayes, 
at Promontories, Capes, and in all Roads, Harbours,& 0 . Which 
way Currents run in all places, with their Times, Changes, &c. 
3. What perpendicular Diftance there is, between the higheft 
reach of the Tide, and loweft of the Ebb , both of all Spring- 
Tides and Neap-Tide?, with their irregularities, &c. 4. What day 
of the Moon’s age, and what times of the Year the higheft and 
loweft Tides fall out .* and all other considerable Accidents obfer- 
vable in Tides, chiefly in and near all Sea- ports, Harbours, Roads, 
Iflands, &c. as St. Helens Ifland^ Bermudas. 5. The pofition of 
the Wind at every Obfeivation of the Tides, &c. 
