पञ्चसिद्धान्तिका (आचार्य वराहमिहिर - सूर्य, रोमक, पौलिश, वासिष्ठ एवं पितामह सिद्धान्त)

XI.5 XI. ECLIPSE DIAGRAM 239 5. Where this line cuts the eclipsed circle (f in the fig.) is the point of first contact. To get the point of last contact also, similar work should be done, using he Moon’s latitude at the time of last contact, marking it on N" – S" line, and drawing the line to the sum-circle in the opposite direction, (i.e. not west ward but earst-ward). (The point of last contact got is l in the fig.) Note: Since the directions are asked to be marked reversed in the case of the Moon eclipsed, we understand that they have to be marked as they are when the Sun is the eclipsed body. The first part of the instructions can be understood to be intended for first contact, since the second part is expressly stated to be for last contact. Since the Moon’s latitude of the moment of last contact is asked to be used to find that point, we infer that the latitude of the moment of first contact is to be used to find the first point. The drawing of lines to the westward rim and eastward rim of the sum- circle can be inferred from the known directions of first and last contacts, keeping in mind that they are marked reversed on the Moon-circle. Thus, the following is the work to be done: (i) In the case of the lunar eclipse alone, mark the directions reversed, on its rim. Take the Moon’s latitude at the time of that particular contact whose point is to be found. Measure it along N" – S" according to its own direction, and mark the point. (In the solar eclipse the latitude is to be parallax-corrected.) (In the fig. these points are L, A, for first and last contacts, respectively.) (ii) From this point, draw a line parallel to E" – W", westward or eastward, respectively, for first or last contact, to meet the rim of the sum-circle, (as in fig, Lf' or Al'.) (iii) Draw f'O or l'O to intersect the rim of the eclipsed at f or l. These are the points of first and last contacts. For example, in the fig, we shall find these: (i) The points of contat for the lunar eclipse is wanted. Therefore N W S E are reversed as s e n w. The latitudes are 19'.35 N, and 27'.65 N. Converted into digits, these are 8.3 and 11.9. According to scale, in the fig., these are 0".8 and 1".2. Measuring along ON", the points marked are L, and A, respectively. (ii) The westward parallel for first contact drawn is Lf', and the eastward parallel for last contact drawn is Al'. (iii) Joining f' and l' with O, the point of first contact got is f, and the point of last contact got is l. Thus, we find from the figure that the first contact is very near the southeast point of the Moon’s rim, and the last contact is a little to the south of its west point. 4b. A.B.विक्षेपान्तद्; C.विक्षेपं तत्; D.विक्षेपस्तत् A.C.D.दिगन्तकं; B.दिगतकं C.०दन्यं स्पृशेन्मध्यम्; D.०दन्यं [लि]खेन्मधात् c. A.B.स्पृश; C.स्पृशद्; D.स्पृशेद् 5b. A.मोक्ष्येण्वेवं B.विपर्ययशोध्यः C.द्वितीये वृत्ते; D.द्वितीयं वृत्तं c. A.खकुध्या; B.खकृतवृध्या D.खकृत्या d. A.०दन्यस्येन्मध्यं || B.०दन्यच्चेन्मध्यान्तसंपाते ||४|| d. A.B.मोक्षत्वा दिक्; C.मोक्षत्वाद् दिक्; D.मोक्षादिक् Really त संपाते belongs to verse 5. A2.विघालव्या