Thursday, 9 June 2016

IS THERE AN ALTERNATIVE TO POENSKOP?

Captain Bruce of the Harlow quoted coordinates marking the last known position of the large steamer astern. He believed this steamer to be Waratah, afire and after an 'explosion' disappeared from view.  I have firmly stood by this view which has taken me on a roller coaster ride with regard to establishing this last known position. Finally the time has come to revisit the confusing coordinates and tighten up the precise position as quoted in period newspapers (1909 and 1910):

 example newspaper extract, 1909.

The agent adds that the Harlow
sighted a smoking vessel at 7.30 on the
evening of July 27, and the explosion occurred 
at 8 o'clock. The distance was too
great for the Harlow to ascertain the ship's
identity. The position of the wreck was
latitude 31 deg. 38 min. south and longitude
29 deg. 55 min. east.

example newspaper extract, 1909:

Captain Weir, of the Clan McIntyre, stated
that he sighted the Waratah on July 27, at
6 a.m., in lat. 31.36 S., long. 29.58 E., which
is (approximately) the position of Cape Hermes. 
The Waratah crossed from the starboard to 
port bow, and went out of sight about 9.30 a.m.

If one uses these two sets of coordinates on Google Earth, the result is crazy but valuable:



An adjustment can be made using the two positions (considerably out to sea) relative to one another as follows:

Distance:6.013 km (to 4 SF*)
Initial bearing:231° 55′ 51″
Final bearing:231° 57′ 25″
Midpoint:31° 37′ 00″ S, 029° 56′ 30″ E

6.0 km is 3.247 nautical miles

If one takes the 'crazy' Cape Hermes position and moves it to where Cape Hermes actually is, this is the distance and bearing between the two points:





In reality the Waratah's last known position is 3.247 nautical miles northeast of Cape Hermes, 0.45 nautical miles short of Poenskop and 0.5 nautical miles offshore.

31 36 33.22 S
29 36 19.02 E

This position coincides with a depth of 20 fathoms (36.5 m) quoted by Captain Bruce. How much more accurate evidence do we need?

I do not believe there is an alternative to Poenskop, which viewed from the perspective of the Harlow greatly resembles the mouth of the Umzimvubu River (St Johns River), but on a smaller scale. When Captain Bruce referred to the mouth St Johns River I believe he was referring to the mouth of the Nkadusweni River.

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