Where are my pumps?

[Bluto 1790]

I'm in the early stages of trying to build a cross section and trying to get the hold area as complete as possible before moving upwards.

The drawings, plans and any other information I have is fairly restricted so there are some aspects I'm 'winging'.

The ship is HMS Leopard from1790, a 4th rate 50 gun ship.

From the drawings I can see the location of the chain pumps but there is no sign of the elm tree pumps.

Here's part of the lower gun deck drawing showing the chain pump cisterns - - - but no elm tree pumps  >

In the orlop drawing (below) are clearly shown TWO pump tubes behind the main mast, although I would have expected to have seen FOUR tubes instead of only TWO, and again, still no sign of any elm tree pumps.  >

There are no drawings or plans of the hold, and in the book "The Fifty Gun Ship", the best drawing I can find is this one  >

While the main mast step is clearly visible in that drawing, most other stuff in the hold is rather vague and I find it difficult to understand everything I see there.

In the following copy of the same photo from above I've highlighted in red what appears to be the chain pump tubes but still can't clearly see any sign of the elm tree pump tubes  >

I'm now having to assume that the drawings in the book are not fully detailed but are only "roughly representative" of all the deck furniture and fittings?

I'm also assuming that there MUST HAVE BEEN elm tree pumps on these 50 gun ships -- but where?

On most other (English) ships of the era the heads of the elm tree pumps all seem to be located immediately ahead of, or adjacent to, the main mast, and the sumps located ahead of the mast step on both sides of the keelson.

So, I'm looking for all you nice guys out there to help me!  Thank you.

[Captain Poison]

Of course, the position on different ships may vary, but if you do not have more detailed information, perhaps this exquisite execution by Dan Vadas can help you ... page 3, post # 68 .

 

 

[Beef Wellington]

Hi Jim, your analysis seems sound.  The pumps would all have been contained within the well around the mainmast, and would need to be forward of the chain pumps and aft of the pillar with the rhodings for the Axeltree.  Any other location would interfere with the working of the fore and aft winches when installed.   The only remaining question is why they are missing from your reference material, and that's a mystery.  I would include them if I were in your shoes. 

 

As to the number of chain pumps, I can only speculate its down to the size of the ship.  There is ample evidence for there being 4 on 1st and 2nd rate ships of the line, and similarly 2 on smaller 5th rates, so logically there must be a cross over point wherever that is.  Don't think I've seen any discussion on that, but 2 doesn't seem unreasonable on a 50 gun 4th rate.

[Mark P]

Good Evening Bluto;

 

Regarding the chain pumps, you are quite correct. Two pump cisterns should equal four tubes, as each pump has a lift and return tube.

 

Concerning the location of the elm tree pumps, I have looked through many deck plans, and they all seem to show only the chain pumps, either two or four cisterns, depending upon size.

 

The extract below is from the deck plan for 'Ardent', a 64 gun ship of 1782. The small octagon adjacent to one of the chain pumps indicates an elm tree pump. 

 

All the best,

 

Mark P

 

[Bluto 1790]

Thanks Capt Poison, Jason and Mark for your help.

 

Captain Poison ~ in the last couple of weeks I've been through Dan's cross section log of vulture at least a couple of times and have pinched a few images from there that will be immensely helpful.

Mark ~ thanks for that image.  I've seen plenty images of the pump heads of the elm tree pumps in so many logs that I've viewed yet it seems to be a bit of a mystery as to what happens below that deck!

Jason ~ I DO intend to include a couple of elm tree pumps up at the lower gun deck level and because of the upper well on orlop deck and lower well in the hold my section will continue to perpetuate the mystery of where the rest of these pumps go!

 

In Dan's log there is this picture  >

There is also this picture  >

While this pic shows the four chain pump tubes, it's not clear what's happening on the far side (forward) of the mast step.

 

I do have another puzzle in connection with the elm tree pumps :  I have read (in a book, not on the internet) that the elm tree pumps exit the ship through the hull for the purpose of drawing sea water onto the deck for hosing and if necessary, fire-fighting.  I have searched the internet, asking the question, but have not succeeded in finding any reference to that water drawing arrangement of the pump(s)  ~  anyone have any information on this?

[davyboy]

Hi Jim,there is a mention of of these pumps for deck washing in Laverys' Arming and Fitting of English Ships of War page 79. They were fitted to all 2 and 3 deck ships and were introduced in 1770. The inlets were 3 feet below the waterline,one per side. He doesn't state where they were fitted though. Midships would be my guess. It was doing repairs to one of these which caused the sinking of the Royal George in 1782.

 

Hope this may be of help to you. Last time I was in Edinburgh half the streets were being dug up for tramlines.

 

Dave   

[Beef Wellington]

According to TFFM the elm tree pumps also terminate in the bilge, very similar to the low point of the chain pumps.  Your identification of the placement for the elmtree pumps is consistent in the photo above.

[Bluto 1790]

Thanks Dave and Jason for your replies.

 

Dave  --  I'm glad I don't appear to be the only one who has read about these pumps exiting through the hull! . . . and it was in a different book in which I read it.  It was "The Anatomy Of Nelson's Ships" but at present I'm having trouble trying to re-locate that statement.

Oh -- and if you were to come back to Edinburgh now you would find the other half of the streets dug up for more tramlines!

 

Jason  --  It would appear that between what you found in TTFM and what Dave found in Lavery's book that there were different locations for the inlets for these pumps.

I know it may sound a bit fatal for a boat or ship having 'holes' in the hull but modern sailing yachts have, on average for a small to medium sized yacht, about five 'holes' for inlets, waste disposal and an inlet for engine cooling water.

[Bluto 1790]

After I posted the above I Googled 'the sinking of the Royal George 1782' and found this  > 

"The Royal George returned to Britain for a major refit in 1780 and saw service with the Channel Fleet thereafter. By August 1782, with the siege still in progress, she was to join a new expedition to relieve Gibraltar as flagship of Admiral Richard Kempenfelt. She was moored off Spithead – the Royal Navy’s Portsmouth anchorage – and was taking on supplies on August 28th when, during deck washing, the ship’s carpenter discovered that the pipe used to draw clean seawater on board was defective. The inlet of this pipe, on the starboard side, was some three feet below the waterline and to access it would demand heeling the ship over to expose it. This was done by running out the guns on the ship’s port side as far as they could go and drawing in the starboard guns, securing them amidships. This action not only exposed the mouth of the pipe to starboard but brought the sills of the open gun-ports on the port side within inches of the water’s surface.

Though the exact number could never be confirmed it was estimated that up to 1200 people were on board, including some 300 women and 60 children.

 

I found the above on this website >  https://dawlishchronicles.com/the-loss-of-hms-royal-george-1782/

 

There's more info on there for anyone wishing to read it.

 

I'm sure there will be other sites carrying an account of this event.

[druxey]

Presumably this is what you are thinking of:

 

https://collections.rmg.co.uk/collections/objects/86635.html

[Bluto 1790]

Thanks for that, Druxey.

 

That's the best description that I've personally seen so far.  That explains why the tubes go right down into the keel area and the inlets are much higher up the hull.  I was a bit mystified by what seemed like 2 conflicting 'solutions'.

 

A few questions if you don't mind.

 

#  Are these some kind of shut-off valves on the inlets just inside the hull?

 

#  At the bottom of each tube (at the keel/keelson) I assume the tubes are completely sealed off?

 

#  Why does the port inlet pipe differ from the starboard at its inboard end in that it appears not to mate with the tube?

 

#  Is that some sort of siphon system for drawing up the water?

 

Thanks for any help coming to this thread.

[druxey]

I'm no expert on the details of these pumps, Jim. However;

 

There appears to be a shut off valve both at F and to the left of G.

 

The tubes to the limber strakes seem to be for flushing or emptying the bilges when required. There would be no logical reason to have a blind end to them.

 

One variation (left side) has the tube simply pointing down to the bilge to flood it when turned on, and the other version (right) has a two-way diverter. Note also the second valve down the tube nearer the bilge end on that side.

 

When there is water in the bilges, it can be drawn up by suction in the usual way that brake pumps work using flapper valves.

[Bob Cleek]

Interesting historical footnote. I'm no expert, either, but I can't seem to come up with a reason the Royal George's carpenter or bosun didn't simply didn't send somebody overboard to knock a temporary plug into the hole outboard. It was only three feet below the waterline on an even keel. That would have made it possible to accomplish the same thing as heeling the ship with far, far less work or risk. I ought to have been the first solution that occurred to any competent ship's carpenter or bosun's mate. 

 

Better yet, I'm wondering whether or not that fact ever occurred to the Board of Inquiry!

[Dziadeczek]

There is a pretty good explanation on the anatomy and function of the elm tree pumps, as well as this so called "flooded cistern system" on pages 142 & 143 in Peter Goodwin's "The Construction and Fitting of the English Man of War 1650-1850". I am attaching a scan of p. 143 here.

Also J. Boudriot talks about pumps in vol. 2 of his '74 gun ship", and even though those are French with small differences of their details, the principle is the same.

Regards,

Thomas

Edited April 4, 2020 by Dziadeczek

[Bluto 1790]

Thanks Thomas for that contribution!

 

I have to say "Wow, this gets more intriguing!" 

 

While I'm now clear as to the routes of the main tubes and the inlet pipes and how the flapper valve system lifts the water, this mind of mine still has some questions!

 

#  In the link that Druxey posted the inlet pipe to port is open ended at its inboard end and obviously floods water into the bilges and I presume that would have been done to flush the stale, stinky water and gunge that accumulated there?  (That water would then be pumped up by means of the chain pumps?)

 

#  If the bottom ends of the elm tree tubes were open into the limber channels then I have to imagine that when the inlet valves were opened the sea would (as water does) find its own level inside the ship which would have been at least half way up the orlop.  This obviously didn't happen, so how was this prevented?  (Was there a non-return flapper valve in the [elm] tubes below the point at which the inlet pipe joined it thus preventing the sea going down the tube?  -- that appears to be the case in the starboard tube in Druxey's link, but the port tube appears to be open all the way down with no valve.)

 

. . . and then there's the 'flooded cistern' system!

 

#  Looking at that, I have to assume that the cistern was fully water tight and didn't allow any water into the bilges?  (I can't think of any other explanation.)

 

#  Do you have any further explanation or illustrations of the flooded cistern system that you could post here?

 

Thank you.

(and thanks to all who have suffered to read this far and endured all those questions!) 

 

 

[Dziadeczek]

11 hours ago, Bluto 1790 said:

Thanks Thomas for that contribution!

 

I have to say "Wow, this gets more intriguing!" 

 

While I'm now clear as to the routes of the main tubes and the inlet pipes and how the flapper valve system lifts the water, this mind of mine still has some questions!

 

#  In the link that Druxey posted the inlet pipe to port is open ended at its inboard end and obviously floods water into the bilges and I presume that would have been done to flush the stale, stinky water and gunge that accumulated there?  (That water would then be pumped up by means of the chain pumps?)

 

#  If the bottom ends of the elm tree tubes were open into the limber channels then I have to imagine that when the inlet valves were opened the sea would (as water does) find its own level inside the ship which would have been at least half way up the orlop.  This obviously didn't happen, so how was this prevented?  (Was there a non-return flapper valve in the [elm] tubes below the point at which the inlet pipe joined it thus preventing the sea going down the tube?  -- that appears to be the case in the starboard tube in Druxey's link, but the port tube appears to be open all the way down with no valve.)

 

. . . and then there's the 'flooded cistern' system!

 

#  Looking at that, I have to assume that the cistern was fully water tight and didn't allow any water into the bilges?  (I can't think of any other explanation.)

 

#  Do you have any further explanation or illustrations of the flooded cistern system that you could post here?

 

Thank you.

(and thanks to all who have suffered to read this far and endured all those questions!) 

 

 

 

 

OK Bluto, here is the previous page nr. 142 from the above mentioned book. This should give you further explanations to your questions.

 

Not being any expert on pumps, I think that the water let inside the hull through those horizontal pipes from the openings in the bulwarks below the waterline, was directed into the watertight cistern, and from there it was sucked up, onto the decks by means of the elm tree pumps, to be used for cleaning the decks and/or for extinguishing fires, or such.  An alternative was to draw water directly from the sea, without this cistern - look on the pic 5/14.

The stale water in the bilges was removed rather by the chain pumps - being more powerful than the elm tree pumps.

 

(also, in the book "The Arming and Fitting of English Ships of War 1600-1815" by Brian Lavery, there is an entire chapter (13 pages!) devoted just to pumps. If you read it, you'be an expert on the topic, for sure!)    :-)

Edited April 4, 2020 by Dziadeczek

[Beef Wellington]

This is indeed a fascinating subject, and unfortunately I have nothing else to add other than musings.  Intuitively it seems inherently a risky design to have the pump directly feed into water outside the keel as shown.  This would make the entire pump case a watertight integrity hazard, failure anywhere in the pump casing below the waterline could result in severe, if not catastrophic, flooding.  While this is clearly something used today in ship design, metal is much more of a robust engineered solution allowing multiple fail safe options in the event of accident or failure.

[Bluto 1790]

Thanks again Thomas for your valuable post and to Jason for your comment.

 

When I first read about the elm tree pumps exiting through the hull my mental image was very similar to the drawing in fig. 5/14 in your post Thomas.  Very intriguing variations for the same end result.

 

Jason, you're right about risk!  Even just going to sea is a risk!  I expect that these structures were fairly robust and for the most part, watertight . . . but any failure and - - oh dear!

Even modern yachts normally have a selection of different sized bungs on board  for whacking into the hull in the case of a sea cock failure.

Edited April 5, 2020 by Bluto 1790

[Dziadeczek]

On p. 142 I scanned above, it is stated that the cyllinders were made of elm, which is very hard and moisture resistant wood, additionally reinforced with iron rings, and this simple construction was very robust, requiring little, if any maintenance, only occasional replacement or greasing of the boxes (valves), so it is quite unlikely that these barrels were susceptible to cracking/ breaking, unless being directly hit by the enemy's fire during a battle. The text also says that  the pump was capable to extract (suck) about 25 gallons of water per minute. I imagine, that if the barrel was cracked/broken, similar amount of water would rush into the bilges. Considering the size of the hull, this wouldn't be so much - after all, there were other pumps onboard to use...

Jean Boudriot says that in French vessels, the working part of this barrel was made from a bronze pipe, only upper and lower ends of the pump were made of elm. As we know, bronze is quite strong, unlikely to crack or corrode. It is used even nowadays for plumbing in certain countries, e.g. Germany...

 

I fully agree with you all, that the life onboard those vessels was very dangerous (not even considering loosing one's life during a battle, where opposing forces were desperatly trying to kill each other!). Even after all these years since then and numerous improvements, it is still one of the most dangerous occupations today!

 

BTW, I found out in B. Lavery's book an illustration, showing a combo-elm pump, which allowed drawing water from both sources, either an inner cistern or directly from the sea. Interesting...

 

Stay safe and healthy,

 

Thomas

Edited April 6, 2020 by Dziadeczek