Friday, 6 December 2013

EXPLORING LEAD CONCENTRATES.


The Advertiser (Adelaide, SA : 1889 - 1931) Wednesday 18 May 1910

THE MISSING WARATAH.
SOUTH AUSTRALIAN EVIDENCE.

"The Collector of Customs (Mr. T. N.
Stephens), in his capacity as registrar of
shipping in South Australia, for some time
has been engaged in collecting evidence in
connection with the missing Lund liner
Waratah."

"Depositions have been taken by
him as a justice of the peace. Some of
the witnesses have been traced with difficulty,
and there are still some to obtain."

"The principal evidence obtained is given
below. Nothing of a sensational nature (I beg to differ),
however, is disclosed in it."

"Mr. J. C. Neill, Port Adelaide manager
for Messrs. George Wills & Co. (agents for
the steamer), stated that while the Waratah
was at Port Adelaide on her inward
passage in June she loaded 1,000 tons of
lead concentrates, which were put amidships in No. 3 hold."

No 3 hold, amidships equates with stabilising dead weight ballast. My thoughts are that these 1000 tons were left there for the return trip (although Mr Larcombe claimed at the Inquiry that 970 tons of lead concentrates were loaded at Adelaide). It also reinforces the Waratah's need for as much dead weight as possible to enhance stability, particularly at the end of a voyage when most of the cargo had been discharged.

"It was not unusual to take on dead weight at Port Adelaide."

'Deadweight tonnage (also known as dead weight abbreviated to DWT, D.W.T., d.w.t., or dwt) is a measure of how much weight a ship is carrying or can safely carry.[1][2][3] It is the sum of the weights of cargo (in this case, lead concentrates), fuel, fresh water, ballast water, provisions, passengers, and crew.[1]'

To understand lead concentrates better we look to Broken Hill situated in the far outback New South Wales where it was mined. Lead concentrates were part of the silver mining process and in fact a high percentage of silver could still be extracted from the lead (Parkes process). This ore was sent by rail to Adelaide for shipping or to the nearest and largest smelter at Port Pirie, about 135 miles distant from Adelaide. Why would 'raw' concentrates be loaded onto the Waratah instead of the processed product unless it was used as ballast?

The following newspaper article refers to 10 710 ingots of copper ore loaded in Adelaide destined for London.

"FROM ADELAIDE

For London -

11,137 bags wheat, 100 bags bark,
1,004 bags flour, x packages wine, 1,107 bags
bark, 183 casks tallow, 1,200 cases dried fruit, 23
cases machinery, x cases eucalyptus oil, 17 sun-
dries, 20 cases crayfish, 500 crates rabbits, 1,238
cases oranges,

10,710 ingots copper ore  *

total insurance on the cargo amounts to

£200,000"

Apart from an additional 300 tons of lead concentrates loaded at this port (see previous post), the Waratah already had her component of 1000 tons - ballast.

Returning to the newspaper article:

"When she returned from the eastern States
she loaded cargo at Ocean Steamers' wharf
and at the Outer Harbour, and in addition
took in 180 tons of bunker coal, which was
placed in the bunkers."

"She had no coal on deck (spar) when she left the Outer Harbour."

Again it is very interesting that no coal was loaded in the spar deck bunker outbound for Durban. This raises the question, why? After all the Waratah was setting out on a very long voyage to Durban, some 5936 miles. It would seem more plausible that all coal bunkers would be utilized for such a voyage (no emigrants on the outbound trip - hence spar deck bunker free for the alternative use - ie. coal stowage). It seems equally strange that the relatively shorter trip from Durban to Cape Town, 790 miles (7.5 times shorter), would require coal loaded in the spar deck bunkers when it was not even a prerequisite for the trans-Indian Ocean passage.

This question is answered in the following post:

http://waratahrevisited.blogspot.com/2015/12/gm-finale-and-conclusion.html





lead concentrates


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