54 ; DISCUSSION OF TIDES IN BOSTON HARBOR. 
Example of the computation of a tidal ephemeris for the first part of January, 1871. 
A a B | Cc c D d | ity e af g i Mf 2 j Bo 
d. h.m. ™m. h. m. hu ut ° | Ma ™ ™ ™ mM. ™. m 
Dec. 30 6 55.0 +2. 7 6 52.3 54 47 | —170 +3) 411.6 44.4 13.0 14.3 0.1 2.8 9.0 
3t 7 36.5 3.2 4 33.3 54 22 0.7 8 10..9 53. 6 12.1 14.6 0.6 2.2 9.0 
dan. 1 818.8 3.7 8 15.1 54. 9|) —0.3 12 959) o8. 3. 10.9 14.8 12 1.7 9.0 
2 9) 207 4.2 8 58.5 54.5 0.0 16 8.5 58. 4 10.0 14.7 2.0 1.3 9.0 
3 9 42.9 4.7 9 44.2 54 10 +0.3 F 19 6.6 54.3 9.1 14.3 2.8 0.8 9.0 
410 37.2 5.1 10 32.1 54 23 0.6 22 4.4 47.1 8.3 13.5 3.5 0.6 9.0 
3 1! 27.5 5.6 11 21.9 54 42 0.8 23 +1.7 37.4 7.6 12:7 4.0 0.5 Ghil 
6 1219.2 6.0 12/13: 9 55° 6 1.0 23) —1.2 Qin 7.0 11.8 4.0 0.5 9.1 
E Al a2 ol k 1 m \th 7 Q | n dn | Ao Al Hy)+A. p qd r \|hhew 
d. h. m. ™m mM. m. m. Mm. | m.| ml Ft. | Ft Ft. Ft. Ft. Ft. Ft. It. Ft. 
Jan. 1 7 30.3 | 52.9 56) Bish) .8 }+1.3 |+05 | 31 § 3.35 ie 55 |—. 52 | 3.87 |+.03 23.96 |4+.18 |+.22 |+.40 | 24.32 
19 57.2 | 26.4 26.0 +0.1 57 | 3, 87 ol 23.95. .45 | 23.50 
2 8 23.2) 48.7 |—4.2 | 24.87 1.2] 0.9 |—0.3} 23] 3.40) 1.50 50 | 3.90 14 23. 99 26) .24 -00 | 24.49 
20 48.0 | 24.3 0.5 | 23.9 0.8 49 | 3.96 07 24.05 .o4 | 23.51 
3) 9) 11-19))| 45:12) | 355) 1 2350 1.6 |+0.4 1159 11 f 3. 61| 1.29 43 | 4.04 19 24.13 34) .24 58 | 24.71 
21 34.9 | 22.6 0.4 | 22,2 1.6| 36 | 4,12 +09 24.21 - 62 | 23.59 
4 9.57.1 | 42.1 3.1 | 21.4 1.9] 0.0 1.9] 55/3 89) 1.01 34 | 4.23 | .20 24. 32 41 24 65 | 24.97 
2218.5] 21.0 0.4 | 20.7 | 2.3 | Q1 | 4, 33 10 24. 42 . 68 | 23.74 
5 10039.2 | 39.9] 2.2 | 20.3) 2.2 |—0.5 | 2.7 | 3714.19) 0.71 24 | 4.43 19 24. 52 47 | .24 71 ) 25. 23 
22 59.5 | 20.0 0.3 | 19.6 3.0 | 62 | 4.52 09 24, 61 TI) OBE GH |) 
(Fabb abbal eehye |) abe) akeoi)) Bssyil (hh) 3.2] 16 4 4. 48) 0.42 14 | 4.62 17 24, 71 49 - 23 12) | 20143 
| 23 38.6) 19.3)° 0.2 | 19.2 | 3.4 42 | 4.70 - 08 24. 79 71 | 24.08 
| 711 57.8 | 38.0 |—0.7 | 19.1 2.3 1.2] 3.5 | 544 4.74 —0.16 |—.05 | 4.79 |+.12 24.288) .49 20 69 | 25.57 
| 8 016.9] 190 0.1) 189 3.9} 20 | 4. 86 + 06 24.95 66 | 24.29 
12) 35. 8 19.0} 2.2 |-1.3) 3.5 32 f 4.92)+0.02 |+.01 | 4.91 25.00 |+. 47 |+.16 |+.63 | 25.63 
| | | | S cos 2B 
rE | Ke uv m' |\t.wh A’, | Hy—A‘| pl q | » | blew} M s hee: Lice: 
j | a Ne sin 2 B | cos 2 B. 
Log. No 
| d.h. m. | m m m m Ft. Ft. It Ht. Ft. Ft Tt, Ft. 
| Jan. 1 13 43.7 |+0.8 |+1.4 |42.2 46 3. 86 | 1.23 |4.11 |4-.08 |+.19 16. 42 | 4.15 | 0.92 9. 644, 9, 9537 9. 9177} —O. 83 
2 210.2 | 2.5 8 3. 88 16.21 «2h 16. 01 
14535565) 152 EGY ||| Pal 38 3.93 16.16 16 06} .22 16. 38 | 3.97% | 0.92 | 9. 862 | 9. 837 9. 801 0.63 | 
| 3 2.0.0} | 2.9| 57} 4.00 16.09 | | 23 | 15.36 | | 
| 15 23.4 1.6 Uabyi| ebal 26 4.08 16. 01 21 }4.03 - 24 16.25 | 3.86 | 0.92 9. 966 9. 582 9.548 0.35 
| 4 3 46.0 3.2 43 4.17 15. 92 «20 15. 67 r 
LG 785) 1-19) Mya} || She 11 4, 28 15. 81 25] .00) |) .25)) 16:06 )— 3:79 | 0.92 10. C00 8. 0907 8. 054n} —0. OL 
5 428.8 | 3.6 25 4.38 15. 71 | ~25 | 15.46 
16 49.3 | 252 )- 155) 3.7 53 4.48 15.61} .28 |—.03 a20. 15. 86 | 3.76 | 0.92 9. 967 | 9. S76p 9.540p) +0. 35 
| G 8 O88} 3.7 6 4.57 15. 52 | .24 15. 28 
17 28.8 2.3) 1.4] 3.7 32 4. 66 15. 43 30 06 24 | 15.67 § 3.78 | 0.92 | 9. 842 9. 857 9. 821 0. 66 
eo 4852 3.7 44 4,75 15. 34 23 15. 11 | 
18 7.3) 2.3 Je3)|) 36 11 4.23 | 15. 26 30 . 09 21 15. 47 | 3.86 | 0.93 | 9. 5017; OTT, 9. 941 0. 87 
8 6 26.4 | 3.5 23 4.289 15. 20 sil) 15. OL | 
| 18 45.3 |-+2.2 +11 43.3 49 4.93 | 15.16 |+.28 \—11 4.17 15.33 } 4.00 | 0.93 | 9. 083p) 9. 99%p 9.965p) +0. 92 
lees ee a ) 
| M-+S cos2B | 2MScos2B |M?24+S?4+2MScos2B 
ie'—Continued. ~——]; |, ae B ab Log. M Log. M2] M2 |M?+S2 = Log. Q 
No. Log. | Log. No. No. Log. 
d.h. m Ft. | 
| Jan. 1 13 43.7 3. 32 0. 521 9. E08p 9. O87p} 0. 618 | 1. 236 17, 22 18. 07 0. 8367) —6. 85 11. 22 1. 050 0. 525 
Pda (5) | | 
14 35.6 3.34 0. 524 9. 826 9.302 } 0.589 | 1.198 15. 78 16. 63 - 701 5. 02 11. 61 1.065 | 0.532 
3 2 0.0 | 
15 23.4 Srol 0.545 9. 930 9.385 f 0.587 | 1.174 14.93 15. 78 - 436 2.713 13. 05 1.116 | 0.558 
4 3 46.0 | 
| 16 7.8 3.78 0.578 9"965 9.388 § 0.579 1.158 14.39 15. 24 8.934n, —0. 09 15.15 ~ 1.180 | 0.590 
> 428.8 ¥ | 
16 49.3 4.11 0. 614 9.933 9.319 § 0.575 | 1.150 14.13 14,99 9. 416p) +2. 61 17. 60 1.245 | 0.622 
@ Gy) 8h} | 
| 17 28.8 4.44 0. 647 9. 809 9.162 # 0.577 | 1.154 14. 26 15.12 0. 699 5.00 20:12 1.303 | 0.651 
| 7 5 48.2 | 
18 7.3 4.73 | 0. 675 9. 462} 8.7924 0. 587 | 1.174 14.93 iby YA) 0.829 | 6.74 | 22.53 1.392 0. 676 
® 6 26.4 | | | 
| 18 45.3 4°92) | 0. 692 9. 051n 1. 204 16.00) 16.86 | 0.86% 4-7. 38 24, 24 1. 385 0. 692 
| 
