I was taught that there are two conventional ways to denote

marine chart positions.

1. The somewhat outdated Deg Min Sec as in N44° 40 (min.) 30 (sec)

written as N44 40 30 with NO decimals

and pronounced as North forty four degrees forty minutes thirty seconds.

This defines a position within 60ft

2. Due to earlier digital eqpt limitations-(they couldn't compute seconds at first)

The modern system of Deg Min Dec. of a Min) as in N44° 40(min) .50

written as N44 40.50

and pronounced as North forty four forty decimal fifty

This defines a position within 60ft.

If you wish to bother with the 3rd digit in your

GPS display of . sec or .01min (both 6ft) then I guess it would be OK to add a dot (decimal pt.) after the 2 digit seconds in example 1. above as:

N44° 40 30.5 & pronounced as

North forty four degrees forty minutes thirty decimal five seconds

though I can't think of a good reason why you would want to.

In the days when degrees minutes seconds were commonly used,no mariner was able to get down to 6ft.

With the advent of DGPS/WASS, 6 ft became possible-& decimals of a minute replaced seconds. as in :

N44°40.505

pronounced North forty four forty decimal five oh five.

When working with old

charts that are marked in degree min. second format,it is advisable to be able to convert seconds to decimals of a minute for communication purposes.

It's very easy:

60sec = 1 minute

30sec = half a minute = .50 min.

15sec= qtr of min. = .25 min

Just divide the actual seconds by 60

This is my understanding for

marine navigation use.

/ Len