276 GEOGRAPHY AND ASTRONOMY. The north-east line in this place must be B P x still gradu- ally inclining toward the several meridians, that so it may make the same angles with the meridians N C m and N A z, as it does with N s s. But by this means you see, that to steer or travel still to the north-east would bring you down to p and x, not to c and A. You see also, that the course you must steer or tra- vel to come to A will be represented by the line a r a, which is much nearer the east point. But this is something too laborious and painful for every reader to trouble his thoughts with it. ProblemXI. " Having the day of the month given, to find the sun's place in the ecliptic." Find the day of the month in the calander on the horizon, (either old stile or new, which soever is required) lay a flat rule on the day of the month, and over against it on the inner hedge of the horizon, will appear both the sign in which the sun is, and the degree of that sign, as on the 10th of May ld stile, the sun is just entering into the first degree of gemini, which you may find on both the globes on the ecliptic circle ; and there you may also compute the longitude of the sun from the point arics if you please. Problem XII. " The day of the month being given to find those placesof the globe where the sun will be vertical or in the zenith that day." Find out the sun's place in the ecliptic circle ; bring it to the meridian ; mark the degree over it ; then turn the globe round, and all those places that pass under that degree will have the sun in their zenith that day. ProblemXIII. f0 The day and hour of the day at one place, viz. London being given, to find at what other place the sun is vertical at that hour." The sun's place for that day being brought to the meridian, and the degree over it, (i. e. the declination) being observed, bring the first place, i. e. London to the meridian. Set lie hour index to the given hour, and turn the globe till the index come to the upper 12, (that is 12 at noon) then the place of the earths that stands under the observed degree of the meridian, has the sun at that moment in the zenith. Problem XIV. rr The day and hour at one place, viz. London being given, to find all those places of the earth where the sun is then rising, setting, or on the meridian, (which is figure, be for the ease of a young learner represented in a strait line, because it is a parallel to the equator, and if drawn round the globe would be a perfect cir- cle and run into itself, yet it stouldmore properly be so far curved, as to cut all the side-meridians N m and_ z at right angles, as well as the meridian of the place n a. And thus they are commonly drawn in maps of the world, wherein there is no line of east andwest drawn strait besides the equator.
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