594 



EXPEDITION TO POINT BARROW, ALASKA. 



Observation* for determining the absolute magnetic declination Continued. 



[Date. Jnne 17. 1882. Instrument, theod. magnetometer No. 11. Mag- 

 net L, ( napendcd. Observers: Cassidy. Murdoch, Smith, and Dark.] 



[Date, Jnno 18, 1882. Instrument, theod. m.i No.ll. Mag- 



net L/, suspended. Observers: Cassidy, Murdoch, Smith, and Dark.] 



Time. 



M.MI. 

 I scale- 

 I readings. 



Computation. 



Mean 



scale - 

 ivadil.gs. 



Computation. 



1 a. in. 



2 a. in. 



3 a. m. 

 4a.m. 

 r. a. m. 

 6 a. m. 

 7a.m. 

 8a.m. 

 :i .1 in. 



10 a. m. 

 1! :i. in 

 12m.... 



54.80 



lil. Mi 

 62.50 

 60.34 

 57.63 

 68.15 

 52.06 



x. :n 



61.67 

 60.18 



Reading of mark. 



At beginning of a. m. ob- J A. 277 06 



serrations < B. 97 04 



' end of p. m. observa- < 



tions 



Reading of mark. 



At beginning of 11. in. ob- ( A. Til 09 



lions. ) B. 97 04 



At end of p. m. observa- J 



tions.. \ 



M,;u, 



277 05.0 



Mi-:.,! . 



277 06.5 



Determination of axis of magnet. 



Determination of axis of magnet. 



Sum = 707.81 



Line of detor- 



15 



A /,. circle 



CA. 51 30 

 }B. 281 20 



Value of one division of scale 

 Scale*reading of axis 



1465. 55 



Mean 



36. G 

 20.7 

 29.0 

 17.8 

 27.0 

 19.8 

 38.0 



50.7 

 36.0 



47.2 

 43.3 



46.7 



43. 65 



39.90 

 32.50 

 35.15 

 31.40 



42. 35 



41.77 

 30.42 

 37.52 

 31.95 

 3R75 



35.06 

 35.16 



as. 01 



33. 55 rej 

 35.07 



Value of one division of scale = 8'. 69 



35.07 



I Line of detor- 



15 



A. circle. 



Scale- reading of axis 35. 07 



Mean scale-reading of E. and 

 W. magnetic elongation. . . 61. 06 



diff.= 



25.99 



Beduction to axis +1 35.9 



Azimuth circle reads 51 29. 6 



Magnetic meridian reads 53 05. 4 



Mean reading of mark 277 05. 



Azimuth of mark 96 13.0 



Trne meridian reads 13 18.0 



Magnetic declination 39 47. 4 E 



[Date, Jnly 19-20, 1882. Instranwnt, theod. magnetometer 11. Mag- 

 not L /( suspended. Observers: Cassidy, Murdoch. Smitb.andDark.j 



I Da I.-. August in. J-*2. Instrument, theod. magnetometer No. 11. 

 Magnet L,, suspended. Observer: A. C. Dark.J 



Time. 



I a. m 



2a. in 



3 a. m 



4 a. m 



5a. m 



6a. in 



7 11. in 



8:1. in 



II a. in 



10 a. m 



11 a. m 



1 p. ui 

 2p.iu 

 3p. m 



4 p. m 



5 1). Til 

 6p. ill 

 7p. m 

 8 p.m 

 9p.m 



10 p. m 



11 p. m 

 12p.m 



Sum 

 Mean 



Mean 

 scale- 

 readings. 



d. 



55. 60 

 46.63 



44.69 

 44.26 

 44.17 

 43. (16 

 59. 31 

 42.65 

 47. 22 

 44.74 

 M. S3 

 44.15 



34.00 

 52.40 

 53.30 

 57.20 

 63.18 

 58.20 

 55.85 

 iil. 99 

 5.1. 60 

 44.95 

 47.82 

 49.72 



. l.lfli). % 

 in. C2 



Computation. 



Time. 



Mean 

 scale- 

 readings. 



Keadiiig of mark. 



\ At beginning of a. m. ob- $ A. 277 28 



diit-ct ) Ji. 97 26 



, At end of p. ui. observa- J A. 97 04 



tions, reversed / B. 277 06 



Mean 



277 16 



Determination of axis of magnet. 



.Scale. 



Scale-read- 

 ings. 



Mean. 



I Altn'tej 



! Mll"lli ' 



35.0 

 10.0 i 

 31.0 

 26.0 ! 



27! 

 36.5 



35.2 

 52.0 

 46.0 

 33.0 

 40.0 

 32.0 

 46.5 



35.10 | 



37. 55 



40.00 ! 30.25 

 29.50 i 40.50 

 41. 00 I 29. 50 



Axis. 



d. 



_">. 50 

 4). 50 



41.25 



34.28 

 35. IS 

 35.00 

 35.25 

 35.37 



1 a. m 



2 a. m 

 3a. m 



4 a. m 



5 a. m 

 6a. m 

 7 a. m 

 8a. m 

 9 a. in 



10 a. m 



11 a. in 

 12m 



Value of one division of scale =r :: . i 



Liin- of detor- 



Sinn ........ 



AT. circle [ A ; 



15 



02 31 



30 

 28 



Sato-reading of axil. . :i."i. ol 3?.iu 



Menu scale-rending of E. and 



\V. magnetic elongation . . 4!l. 02 



din". = 



.n to axis -H 



Azimuth circle reads - "'2 20.2 



1 p. m 



2 p. m 



3 p. m 



4 p. m 



5 p. m 



6 p. m 

 7p.m 

 8 p. m 

 9p.ni 



10 p.m 



11 p. ui 



12 p. m 



d. 

 31.28 



:!!i. r.r. 



37. 64 

 38.64 

 35.38 

 39. 10 

 39.38 

 37.00 



37.46 

 35.03 



38.51 



37.28 

 29. 01 

 67.48 

 58.88 

 46. 18 

 43. 48 

 47.60 

 52.81 

 42.66 

 33. .% 

 41.32 

 18.61 



Computation. 



Reading of mark. 



At beginning of a. m. ob- C A. 



servat ions ) B. 



At end of p. m. observa- (A. 



tions )fl. 



Mean. 



56 

 54 

 A3 



H 



359 53.8 



Determination of axis of magnet. 



Altn'te 

 mean. 



MaLZla t i< im-ui!,:i,. i ruils 53 23.0 



.H'MII, nl n::u K 277 10. (I 



A/.imutliof mark IX; l::. o 



True raertdtao reada l:! 2:1.0 



.in -linai -.11 ::'.! M. K. 



I.ini- of d. -tin - 



ir. 



32.0 

 5.7 

 33.2 

 2J. 2 

 16.5 

 17. 5 

 36.0 



39.0 

 51.0 

 49.5 

 35.4 

 85.0 

 40.2 

 47.0 



35.50 

 28.35 

 41. 35 



28. 80 

 40.75 

 28.85 

 41.50 



38.4:! 



41.05 



1 71) 

 41. 13 34. M 



Value of one division of scale = 3'. 69 



leading of axis 34. 92 



i-uii Bella-reading of E. and 



W. magnetic elongation. . . 41. :i"> 



dill'. 



6.43 



ion to axis ......... - ; 



Aximnth circle teada ....... 354 09.0 



10 



08 



nl' mark ...... 3" ( ' 



Aziunilliof mark ........... 46 36.0 



Trne meridian reads ........ 313 17. x 



Magnetic declination 41 . i. it K 



