Co-tidal lines of the Atlantic Coast of the United States. 6 
Iam indebted to L. F. Pourtales, Esq., in charge of the tidal 
party of the U. S. Coast Survey, for the revision of the compu- 
tations given in this paper. The labor of reducing the observa- 
tions themselves has fallen chiefly upon Messrs. Heaton, Fendall, 
and Hawley. The diagrams have been prepared by Mr. C. Fen- 
dall, under the direction of Mr. Pourtales. 
TABLE No. 1. 
Observations for co-tidal hours, 
Stations, piper Years. Remarks. 
Sable; N.S. ..... : - 
enwood'’s Island, N.S... ...1.cd.ccssccseees peer by Copiein Phers 
Bourchue Island, N.S...) . i. ....2sfecdcasecss os irate tee 
Portland, Me. ......... 6i ° (1962-3. ...-.8 Self-registering. dion 
‘ee beagle oe 
Portsmouth, N.H...... 14. |1851-2-8...22- jierte pean cpeokiyretall 
Newburyport, Mass.. . 2 1851-2. .....4 
i Mt teae a 2 18 
“jGloucester,........... 1 1853 
ere ee 24 1850 
Boston Light,......... 34 1847 Si oc .|Results reliable. 
ton Dry-dock,...... 64 yrs1847-—53 Best series. 
e ian aac ple 1 349 4 
Provincetown,......... 10 [888-4 6 From Maj. Graham’s survey. 
Monomoy,............ if 52 ail 
reat Point, Nantucket, 14 349-50 . 4004 
SOE ces eo 3 g58—4., Eee = 
antucket Harbor,..... 13 1846 to 1850... /Irregular. 
Tuckernuck, ........., 1 [S50 0. aces 
Wasque Point, ..... BA te ss 185 
Edgartown,........._. 7 1846-7~51-2 .. 
Oe ERONO, eh |e 6 1846-51-22. 
Wood’s Hole (east), .... 3 1849-52 . gat 
ulin Cove,....... 3 1849-51... us 
Quick’s Hole (south), .. 2 351 
sha Bight, ...... 1 852 
ON ile oot 16 184446 2.0... 
| 544-8. cs cde os 
| Eee 25 848 i 
Montauk 3. ee 24 848 Not a good series. 
| land, er ee ea 2 850 Nota good series. 
carne ee 7 8835-64451. 
Cold Spring inlet,...... 11 oy, Pee e Day tides only. 
May landing,..... 2 
Delaware breakwater,..| 10$ [1840-41434 
cheery Comfort,..... 65 1846-61. 2... 
| eg ee cha 
Fe | * wiaiagge ttt ee eee 9 W618 Ae 
. Pe ae Peper 
| eae 6 a a 
; os ee 13 1851 
; 1 jI853 ec eecus ; 
11 tides.|1850 Quite unreliable. 
gc oe NOS 
The Stations at which observations of the tides have been made, 
of the more reliable class are thirty-three in number, extending: | 
