Monday, 25 April 2016

3456 TONS OF COAL OUTBOUND - REVISITED.

In a previous post I explored the issue of 3456 tons of coal on board Waratah when she departed London on her second voyage. It appeared to me both confusing and irrational. After the maiden voyage it was clear that Waratah was tender - low GM. It was an issue that was discussed and presented to the builders who suggested filling ballast tank 8 - 222 tons - to improve dead weight lowest down, thus reducing the centre of gravity and improving GM. They also suggested avoiding loading coal in the 'tween decks reserve bunkers - a very significant 873 tons at 42 cubic feet to the ton. After all of this I was astounded that Waratah departed London with 3456 tons of coal, when total coal capacity, permanent and reserve, was 3829 tons, implying that at least 241 tons had to go into spar deck bunkers, 'tween decks and in my opinion creating a disaster for GM. It seemed to me to be so extreme that I could only imagine that coal shortages or coal prices forced the Lunds to expect Waratah to depart London in such a condition. But then I came across an illuminating comment:

 Mr. William. H. P. Baker, of Dover
street, Richmond, who (says the Melbourne 
Herald) was an able seaman
on board the missing steamer Waratah,
on her last voyage to Australia,

....."We had about 4000 tons of coal in the main 
hold when we left London."

The penny dropped. 

The incorrect assumption made was that coal had to be loaded into coal bunkers. But according to Mr. Baker, 4000 tons (roughly the 3456 tons referred to) in its entirety were loaded into the main hold, assuming this refers to the predominant lower deck hold/s and not the main deck hold/s. If this be true, it makes sense in view of the fact that coal in both bunkers and cargo holds low down would have had a stabilising effect. Coal displaced cargo on the outbound voyage, which also makes sense given that the principal cargo volume was inbound from Australia. Coal was therefore not necessarily loaded into 'tween decks or the spar deck for that matter. There were no coal shortages or price issues. 

Alfred Pinel commented on this voyage that Waratah rolled very heavily crossing the Bight, which makes sense considering that the bulk of the coal in the lower hold was burned out reducing GM.



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