Co-tidal lines of the Atlantic Coast of the United States. 21 
ward, re-appearing again north and east of Hatteras, and following 
the coast inwards towards Sandy Hook, and then towards Point 
Judith, and leaving the coast off the shoals of Nantucket and 
Cape Cod. The lines of 114’. and LIA. are approximately drawn 
outside of the line of 12h. which, in general, is quite near to the 
a and conforms to its sinuosities from Tybee to Narragansett 
entrance, 
TABLE No. 3. 
ae Pia [id 
Erato 
E | 239,13 gs 
& a eae ls. 
3 3 | oN weeGlese 
& Groups of stations. a wie fa rab ss 238 
7 g $25 2538 
= Fy SEE sixes 
- & 222 21565 
| a Sr a en Hat 
: h.m eee ae : 
{2 -..|Pive stations from Savan-|11 52} 1-303, 50 '9} 125 | 24 |Tybee, Charleston, Cape 
|... |_mah to Hatteras. Fear, Beaufort, Hatteras. | 
- jabis. bie gee uncorrected for|12 16} 1-298} 5223) 2:31 13 |: 
epth, it 
Be... Four stations from Old!i2 18} 0-411) 2221) 4-47 6 |Old Point Comfort, Dela-| 
Point Comfort to Sandy ware breakwater, Cold) 
OOK. Spr’g inlet, Sand Hook,| 
¢.../Four stations from Sandy|12 6 2-00 | 6327) 0-76 40 |Sandy Hook, Point Jud- 
Hook to Quick’s Hole. ith, Beavertail, Quicks’ 
: ee ole. 
c bis.Six Stations from Sandy|12 10} 1-638) 58 36 0:13 | 231 |Sandy Hook, Fire island,| 
Hook to Quick’s Hole. Montauk Point, P’t Jud- 
ith, Beavertail, Quicks’ 
— Hole. 
+. /Six stations from Prov-|15 15| 0-608 3117) 0-924} 32 |Provincetown,Wellfleet, 
Incetown to Cape Ann. oston, Na hant, Salem, 
€.../Six stations from Cape Gloucester. 
Ann to Cape Sable. |14 37) 0968 44 4| 1-006 | 30 |Newburyport, Portsm’th, 
Portland, Fourchue is}- 
and, Ellenwood’s isl- 
and, Cape Suble island. 
3846} 0910] 33 
2 48'- 0-514'117 12! 1°05 29 |St. John’s river, Cape Ca-| 
naveral, Cape Florida. | 
bis. Twelve stations from Pro-|14 56) 
incetown to C. Sable. 
if aha stations, pas: 
a 
2 
s 
o 
1 
i 
The co-tidal line of 15h. isthe one which characterises the in- 
dentation between Cape Cod and Cape Sable, the probable con- 
eee of the depth of the sea there, and of the co-tidal lines, 
ace traced on the chart. ‘The lines connecting these two sys- 
ems are uncertain. ‘The tide-wave appears to move backward 
Meet but chiefly to learn whether stations must be multiplied 
ti observations repeated ; and it is not necessary to occupy the 
me of the association with a detail of these trials, or with their 
vaults. ‘They will be used in the progress of the further one | 
