-l|-l|-l-

I  '    o|-i-i  +1  +  3!  +

7+    9

^±

-♦-

6  +

1  —

3-   4i-

6-  5|-

4'-

3-  2

_-   1    0-

June.
1889     1

-ll     0

0

0-1

_2L2-2'       0  +

4+6

+   6

+

•^1  +

8  +

1-    4-

4

-    4'—

2-

1-1!

-  1     0

1890

-1-1

0

—

l|-4

-41-3-2        0  +

4+7

+   9

+

9  +

6  +

1,-   3-

5

-   6-

8-

2-2

-  -3-1-

1891
Mean.
-1  +1

0

—

1-5

-6-6-4  +    1  +

1                       1

8+12

+  14

+  16|  +  12  +

9'-   1-

3

-   8-

8-

^-1

_  6-5h

-1

0

0

—

1

-3

-4-4-3

0  +

r»  +  8  + 10

+  10  +

7|  +

4-   3  —

4-  6-

4-

3-   3

_  8-2-^

1  Mean  of  6  days  only.
'i  January  1890  lacking.
HABYLAND  GEOLOGICAL  8UEVEY


60


Table  XII. — Concluded

j0ittrna}  rariation   of   the    vertical  intentity  of  the  earth^t  magnetic  force  a»  derived  from  the  continuous  obMrvatiofiB

at  the   Wa$hingt<m  Magnetic  Observatory  from  1889-91.
TLf  quantities  are  expressed  in  units  of  the  fifth  decimal  C.  G.  8.  Bystem,  and  are  given  for  hours  of  75  Meri-
ian  tinae  which  is  Sm.  12s.  fast  on  local  mean  time.  Plus  sign  indicates  less,  and  minus  sign  greater  than
lean  of  day.
HOURS.
'k

A.M.
P.
M.
