ASSEMBLING TERROR’S STERN

I haven't posted an update regarding my model in several months. While I've kept busy with side projects, the real reason for my delay is that I had reached an impasse with Terror’s stern.

As I've discussed in previous posts, the sterns of Franklin’s ships were modified in 1845 to accommodate a new auxiliary screw propulsion system – to be used as a time saving device “providing the wind should prove contrary or a dead calm” [1]. There are two sources of data on these modifications: Oliver Lang’s original design plan [1], and its counterpart, a contemporary model of the design [2]. I had purchased full resolution copies of the plan many months ago, but unfortunately Lang did not include a cross section in his draught. That information could only be gleaned from the contemporary model held at the National Maritime Museum’s storage facility in Chatham.   

The contemporary model of Oliver Lang's 1845 design. 

National Maritime Museum, Greenwich, London (SLR2253 [L2251-001]).

Used under Creative Commons Attribution-Non-Commercial-ShareAlike (CC BY-NC-SA) license

Fortunately, I recently had an opportunity to visit the Chatham model ship facility. Assisted by the expert curators, I was able to study the stern model in detail. It is quite unique, being constructed using a series of carved blocks arranged to conform to the position of major structural and engineering elements of Lang’s design.  The information I gathered has allowed me to complete my construction of the stern;  below, I’ll reveal the new information I've learned from the contemporary model, while documenting my final assembly of Terror’s stern:

1) The propeller well used to raise and lower the screw was rectangular, almost square-sided, with the sternpost and rudderpost forming the fore and aft sides of the well, respectively. To accomplish this, thick timbers were bolted to the sides of the rudderpost and sternpost [3]. The rudderpost bolsters were much more complex than I originally assumed and were each constructed of at least two pieces, with the lower portions tapering gently to the width of the rudderpost, following the lines of the body plan (see here for my original conceptualization of the design).

The stern pieces prior to assembly. The bolster on the left is the old design I intended to use, which was incorrect. 

The overkill method I used to glue the bolsters to the stern and rudderposts. Thankfully this was just a dry-run
(note the older bolster design). 

The  new bolster timbers glued on the rudderpost. Note the groove for the "Lihou" rudder on the
rudderpost. I may need to sand the bolsters somewhat to match the run of the planking as they
may be slightly oversized - but no by much. 

Another angle showing the bolster timbers on the sternpost. The NMM model shows that the bolsters on the
rudderpost are longer than those on the sternpost. 

2) The rudderpost and sternpost were each tenoned into the keel extension, as was typical, but each was secured with a single bolt, which was not indicated on Lang’s plan.  

Marking the precise position of the tenon bolts. 

The bolts were simulated with 20 gauge copper wire, precisely the same as that used on the keel scarphs. 

3) The propeller well was framed on the port and starboard sides in three distinct sections. The upper section included stout rectangular framing fayed to the deck beams, which formed a ledge for a scuttle on the upper deck. Below this, the well was probably enclosed by watertight planking down to the height of the stern timbers. Because of the construction of the contemporary NMM model, such planking was not shown, but it is unlikely that solid timber pieces would have been used, as these aren’t shown in contemporary models.

The heavy framing used to form the top of the propeller well. The upper part of these timbers formed a lip
for a scuttle to the well. 

Planking on the upper section of the well. I've estimated a width of 12 inches. The actual width is unknown.
Note that this section of the model will be covered so I haven't simulated bolts or spikes here. 

A view of the topside of the well. The upper pieces of the sternpost and rudderpost bolsters will be
trimmed at a later stage of the build , but are useful for alignment at this stage. 

4) A new section, clearly visible in the well of the model, started at the position of the stern timbers. This suggests the stern timbers were bolted to the sides of the rudderpost and sternposts to provide major structural support to the new rudderpost and well. This makes good sense, and Lang’s 1845 stern plan clearly shows the stern timbers as a major element of the design. In fact, these new timbers are substantially more robust than Terror’s original stern timbers, suggesting they were an integral part of the strength of the new structure. Again, this type of structure is supported by contemporary models.

The bottom portion of the framing planks were trimmed to match the run of the stern timbers. Note
the rabbet on the rudderpost on the right. 

5) The lower section of the propeller well was composed of the second layer of hull planking where it ran aft, horizontally.  Eventually, the run of the higher planks would have veered away from the straight-sided wall of the well. At this point, straight horizontal planking would have been used to frame the sides of the well. The position where this occurs is marked by a block seam on the contemporary NMM model.

Unfortunately, Lang’s contemporary  model does not include any of the ironwork used to strengthen the stern, nor does it include the propeller rail/track mechanism. I've based these portions of the model on Lang’s plans and extensive research on other contemporary models and designs. This research is outlined in several blog posts (and here, here, and here).

Oliver Lag's stern design. Note the extensive ironwork and the propeller systems.

National Maritime Museum, Greenwich, London (ZAZ5683 [J1529]).

Used under Creative Commons Attribution-Non-Commercial-ShareAlike (CC BY-NC-SA) license.

The iron staple knee glued in place. The knee provided essential support for the rudderpost. 

Mini-Crozier inspects the staple knee in dry dock. 

Lang used iron strapping to further reinforce the stern structure. Here they are made from chemically blackened copper. 

Each strap was glued in place and then the bolt holes were drilled out by hand. 

Bolts glued in place. These were simulated using blackened brass. 

Another view of the completed iron work.

Mini-Crozier frets over the modifications. 

The staple knee was protected by a fitted  chock bolted to the keel section. I carved this using a simple
chisel blade. 

The finished chock compared to the plans. 

Image showing how the chock fits over the knee. Unfortunately it had to be glued in place to permit 
the propeller rails/tracks to be installed. At least I know the knee is there. 

The chock glued in place.

The propeller was raised and lowered using rails or "tracks". These have been modified slightly
from my original versions based on new data. Copper bolts were simulated using wire. 

The rails glued in final position. Note  the  rabbet on the rudderpost 
for the second layer of hull planking. The rabbet will be modified  to 
accommodate the precise run of planking when it is installed. 

 View of the rails installed on the sternpost. 

View of the rails installed on the rudderpost. 

Another view. 

Wooden bolt plugs added to the chock. The bolts were "counterbored and plugged".

The staple knee was bolted to the rudderpost; these bolts were also counterbored and plugged.
I'm not entirely happy with the contrast here and may redo them at a later date.

The completed stern assembly.

Lowering the screw propeller in place (it raise and lowers - and the propeller spins). 

The propeller in position. Unfortunately the angle of the photo makes it look slightly crooked,
but it is not - is spins freely, with very small tolerances as shown on Lang's original plans. 

A view from the stern.

Another angle showing how the propeller was seated.  

Looking down the well from the position of the upper deck .

Mini-Crozier contemplates how the stern will fare in the ice. 

How successful was Lang’s stern at protecting the ship from the pack ice? Parks Canada divers are assessing that currently, and with luck they’ll find the answers soon. We know from historical sources that the Admiralty was concerned about the strength of the design, and that while Lang believed the “sternposts” (sternposts and rudderposts) were as strong as those on other ships, he would not certify that the strength of the filling chocks was sufficient to protect the Erebus and Terror [4].

No matter how vulnerable it made the ship, we can suspect that Lang’s radical redesign also altered the sailing qualities of Terror. Contemporary sailing reports indicate that Vesuvius class bomb vessels were rather lumbering and could not carry sail well, and Ross reported that Terror was constantly falling behind Erebus during his Antarctic voyage, delaying and endangering the expedition.

Recently, Regina Koellner, assisted by William Battersby, transcribed a letter [5] from Francis Crozier to his friend John Henderson, written shortly after the ships arrived at Whalefish Islands in Greenland. In the letter, Crozier provides a brief report of Terror’s sailing qualities: "Our steering is decidedly improved by the alterations on the counter we now sail much more evenly with Erebus which is advantageous to us in many ways." I suspect that the effective lengthening of the keel to accommodate the propeller allowed Terror to sail closer to the wind, finally permitting her to keep up with the more nimble Erebus. It seems the final conversion of Terror to screw propulsion made her a more capable vessel under sail, an irony certainly not lost on Crozier.

Acknowledgments:
I sincerely  thank Regina Koellner for permitting me to post the transcription from her recent research, and William Battersby for alerting me to this exciting primary report on Terror’s sailing qualities.


Footnotes:

[1] Object ID: ZAZ5683

[2] Object ID: SLR2253

[3] Filling frames, similar to fashion pieces, appear to have been fayed to these bolster timbers on the sternpost to accommodate the smooth run of planking over the upper part of the well. My belief is that space between these frames and behind the transom pieces was filled in with chocks, similar to the bow, to add more strength to the stern.

[4] Admiralty Digest, cited from Battersby, William, and Carney, Peter, 2011, Equipping HM Ships Erebus and Terror, 1845. International Journal for the History of Engineering & Technology 81(2):192-211.

[5] AGC/C/5/; MS62/007

MR. DIGGLE’S GALLEY STOVE

I haven’t updated my blog in some time, as I have been busy with several exciting side projects, which I hope to reveal here in due course. In the meantime, work continues on my model and plans when I can find time. The stern of Terror is almost completed and I’ll post my progress here shortly. I’ve also recently finished elevations/profiles of fittings located on the forward crew deck, including the sail bin, the mess tables, and crew trunks/benches.

One problem with drafting elevations in this area of the ship has been a lack of information on Terror’s galley stove.  We know that Terror was fitted with a “Fraser’s patent” stove for its 1836-37 Arctic expedition and that both Erebus and Terror were fitted with these stoves for the 1839-1843 Antarctic voyage. It is widely assumed that the same stoves were used for the Franklin Expedition.

Both the 1836/1837 (Terror) and 1839 (Terror and Erebus) plan sets show an iron stove of the same size and shape, with forward facing boilers, a rather large hotplate, and three access doors on one side (starboard). Both sets of plans show a water tank hanging from the upper deck beams directly over the stove, and in the 1836/1837 plans the stove is connected via a short pipe to the tank (for an excellent review of how this tank functioned please consult Peter Carney’s blog). However, the 1839 plan set shows an additional box-like projection with rounded corners abutting the front of the stove. The projection has a forward facing door, and seems to be designed to articulate with the stove’s fireplace, while being a separate accessory.

Fraser's patent stoves as they appear on the two HMS Terror plan sets. Note the
additional device attached to the 1839 stove.  

Prior to Terror’s first polar voyage in 1836, James Fraser held four patents associated with stoves. The first, numbered 4201, dated January 15th, 1818, described a very complex ships’ fire hearth and desalinator which incorporated iron boilers and stonework. His next patent, #4310, dated November 13th, 1818, detailed a brick and iron domestic (land-based) fire hearth and boiler. His third and most successful patent, # 4706, dated September 27th, 1822 (shared with  John Moxon), outlined a design for a contemporary galley similar to a “Brodie stove” used in Royal Navy ships since the late 18th century. His final pre-1845 patent, #5762 dated January 27th, 1829, described a radical redesign of his iron ship and domestic stoves (to my knowledge there is no evidence that the 1829 device was ever used on Royal Navy vessels).

Comparing the Royal Navy draughts to Fraser’s patents indicates that his1822 patent [1] design closely matches the general shape and dimensions of the stoves installed on HMS Terror in 1836 and 1839. Fraser’s stove was intended to be compact (the 1822 patent is for a narrow, half-width stove) and was therefore only suitable for smaller vessels such as brigs and merchant ships.  Beyond the narrow width, the major difference between Fraser’s 1822 patent and the 1836/1837 Terror plans is the position of the boilers. In 1822, there appear to have been two differently sized boilers (coppers) arranged from front to back.

An engraving of Fraser's 1822 patent. Note the front to back arrangement of the boilers.

An 1833 engraving of a “Frazer patent sort” [2] stove indicates that Fraser later increased the width of the stove and placed two identically sized coppers side by side, thereby increasing the size of the hotplate at the front of the stove while reducing the size of the oven which shared the warming flue with the boilers.  This 1833 sketch is in fact very similar to the stove depicted on the 1836/1837 Terror plans.

An 1833 engraving of Frazer's updated design. Note the side by side boilers,
larger hot plate, and smaller oven space. 

A significant attribute of the Fraser stove was the inclusion of folding or removable plates that could be closed down over the fireplace during bad weather. Previously, ship stoves had to be put out in stormy weather due to risk of fire from stray embers. This seems to have been a critical selling point, and in 1830 Henry Beeston and Company, who held the manufacturing rights, marketed the stoves as the “Fraser’s safety ships’ hearth” [3] (by 1831 the Beeston company was bankrupt and Fraser assumed control of sales and manufacturing thereafter).

My interpretation of the appearance and design of "Fraser's Patent Stove" on HMS Terror. The plans incorporates

scale details from the 1822 patent, the 1833 engraving, and the HMS Terror plan sets.

An assessment of the Fraser stove appears in a report from the voyage of HMS Chanticleer (1828-1830) and is worth noting in its entirety:

“This …Frazer's [stove]… has undergone a three years’ trial on board the Chanticleer

and its qualities have been the constant admiration of everyone on board.  The

provisions were cooked by it in bad weather and in a boisterous sea equally as

well as if the vessel had been in harbour; and although the hatches might be

battened down, no inconvenience whatever was experienced from it,

an advantage which can only be fully appreciated by those who are accustomed

to small vessels. The consumption of coals which served for the culinary purposes

of the whole crew for one day amounted only to one bushel… On the whole,

Frazer's stove may be considered as a most valuable acquisition to a ship.“[4]

The stove’s success on Chanticleer cemented its association with survey vessels and a similar model was ordered in 1831 for HMS Beagle’s famous second voyage. HMS Terror appears to have been the first polar exploration vessel to adopt a Fraser stove, which was installed for the 1836 Arctic voyage under the command of George Back. He praised the device,  “…which, besides throwing out more heat than those commonly in use, had the decided advantage of consuming less fuel, and [was] therefore particularly desirable in a ship with a limited quantity of coals”. [5] Back admired the design so much that he dismantled the malfunctioning hot water furnace on the orlop deck and used its materials “for fitting up a Fraser’s stove a little before the main-hatchway on the lower deck” [6]. Given what he had to work with, it probably looked much like Fraser’s early 1818 brick and iron patent.

Having functioned so well on a polar ship, it is not surprising that the stove was adopted for the 1839 and 1845 voyages of Erebus and Terror. Pencil annotations on the 1837 lower deck plans of Terror indicate that the old Fraser stove was crossed out, and a new stove precisely the same dimensions and shape as the 1839 plans was drawn in, somewhat aft of its original position. The stove is labeled in pencil as “Fire Hearth, Fraser”; the new box-like projection was labeled as well, but it is impossible to decipher the heavily worn inscription.  However, the label appears to have consisted of two words, with the last word starting in an “O” or “D”.

What was the additional device added to the Fraser stoves in 1839? Interestingly, a clue may come from documents relating to HMS Beagle [7]. Navy correspondence from 1831 indicates a new stove was purchased for Beagle directly from Mr. Fraser, at a cost of £ 46.10s, and was delivered around the 19th of July of that year.  However, it appears that Fraser included an additional device in the shipment, as noted by Captain FitzRoy:

“Hamoaze, 24 Aug. 1831.  I beg to inform you that the patent Galley Stove

made by Mr. Fraser of Shadwell for the use of the Beagle, is furnished with

an additional bread oven which I find increases the expense £ 17.  As this oven

will be of the greatest use in baking bread for the Ship's Company, I hope it will

be allowed by the Navy Board without my paying for it myself.” [8]

In his later account of the voyage, FitzRoy makes it clear that this additional device was not a standalone piece and articulated directly with the Fraser stove: ”…one of Frazer's [sic] stoves, with an oven attached, was taken instead of a common “galley” fire-place…” [9]

Could the accessory on the Terror’s Fraser stove have been a bread oven? Most 19th century iron galleys were designed to accept accessories at the front of the fireplace, including meat spits, racks, and various other attachments. In fact, Fraser’s 1822 patent shows brackets of a sort commonly used to attach such devices. Although the labelling on the 1837 plans is unclear, it is possible that the accessory was a bread oven, though it could be another type of a more common cooking accessory, such as a hastener or hot closet.

As far as I am aware, only one Fraser stove is known to have survived to modern times, and it is sitting on the lower deck of HMS Erebus, at the bottom of Queen Maud Gulf, in roughly 12 meters of water. Hopefully, this fascinating piece of Victorian technology – which played a central role for the crews on some of the greatest sea voyages ever conducted – will be revealed by Parks Canada in the coming weeks.

Terror's galley stove was quite small, as indicated by a scale Captain 

Crozier. The height between decks in this area was only six feet.

Note the position of the water tank.[10]

Acknowledgments: William Battersby and Peter Carney have been exploring the heating and cooking systems of HMS Terror and Erebus for many years, and they have been very generous in sharing data and insights with me. Peter, in particular, has studied the design of the Fraser stove in depth and his research on the role the technology played in Franklin Expedition is a must. Peter kindly reviewed my plans and research for this post, and provided access to crucial patent engravings.  I sincerely appreciate his critical insights.

Footnotes:

1: Moxon, John, and Fraser, James.  1824. Patents for Improvements in Ship’s Cabouses, etc. The Repertory of Arts, Manufactures, and Agriculture. London: Repertory Office. Pages 268-275.

2. E.W.B. 1833. Apparatus for Freshening Salt Water. Mechanic’s Magazine, Museum, Register, Journal and Gazette. No. 501, Saturday, March 16, 1833. London: M. Salmon.  Pages 335-336.

3. 1830. The Law Advertiser, Volume 8. London: J.W. Pagent. Page 465.

4. Webster, William Henry B. 1834. Narrative of a Voyage to the Southern Atlantic Ocean, in the Years 1828, 29, 30, Performed in H.M. Sloop Chanticleer, Volume 1. London: Richard Betley. Page 6. 

5. Back, George R. 1838. Narrative of an Expedition in H.M.S. Terror, Undertaken with a View to Geographical Discovery on the Arctic Shores in the Year 1836-7. London: John Murray. Page 5.

6. Back, George R. 1838 Narrative of an Expedition in H.M.S. Terror, Undertaken with a View to Geographical Discovery on the Arctic Shores in the Year 1836-7. London: John Murray. Page 150.

7. ADM 106/1346

8. ADM 106/1346

9. FitzRoy, Robert. 1839. Proceedings of the Second Expedition, 1831- 1836, Under the Command of Captain Robert FitzRoy, R.N. Narrative of Surveying Voyages of His Majesty's Ships Adventure and Beagle, Between The Years 1826 And 1836, Describing their Examination of the Southern Shores of South America, and The Beagle's Circumnavigation of the Globe. Volume 11. London: Henry Colburn. Page 18.

10. The iron water tank hanging above the Fraser stove in both sets of Terror plans appears to have been suspended from a deck beam (or beams), with the tank lid positioned below the standard ship’s air-scuttle. Its precise position likely varied between Erebus and Terror - in relation to the framing and deck beams associated with the air scuttle. It is possible that the tank had a central opening or one near the side, depending on its position in relation to the beams and scuttle.

NEW YEAR’S UPDATE

It has been a busy year for my project, though, unfortunately, much of my work  hasn't translated into recent blog posts. As most of my readers know, my project is really two in one: to create the first accurate scale model of HMS Terror as she appeared in 1845, and to produce the first accurate plans of the ship in her 1845 configuration. I spent much of the year on the latter, having decided early in the year to extend my plans to all decks and fittings of the ship. I completed a significant amount of this work, including the lower deck plans and details of accommodations (I’ve produced much more than has appeared on my blog), and I am nearing completion of plans for the orlop deck and hold, as well as various cross sections. As always, creating these plans is not as simple as tracing the original Terror/Erebus plans, as each requires significant historical research to fill in the many missing gaps. 

The discovery of HMS Erebus by Parks Canada also had a significant impact on my project. My blog was inundated with thousands of views and I received many dozens of emails from interested readers, researchers, and other enthusiasts. Many came during the exciting few weeks between the time the ship was discovered and when it was eventually identified. I enjoyed these exchanges immensely and they led to a blog post about the structural differences between the ships, which received a very positive response from many readers. 

The discovery also led to several requests for consultation/information/plans from researchers involved in various media projects. I’m very excited by some of these new projects and while I can’t disclose them all yet, I’m sincerely gratified that my research will appear in formats other than my blog . One of these has already come out; Canadian Geographic Magazine requested a modified version of my plans showing the most important ship systems. They did not utilize the entire plan, which included a cross section, so I have provided the entire image above for readers. 

Despite all of this additional work, I haven’t forgotten about my model, and I’ve been working slowly away at it when I can find a chance. Below I outline my progress to date: 

Each scarph on the keel had 8 copper bolts, 1 and 1/8 inches in diameter (consistent with much larger 36 and 74 gun vessels). I simulated these using 20 gauge copper wire which accounts for a 1.5 inch rove. 

Gluing the main keel and stem together. Alignment was critical, so the parts
were laid out over the plan and clamped/weighted down.

Checking the alignment before gluing. The unfinished profile piece can be seen in the background. 

Gluing the pieces in place. 

The completed keel/stem assembly with the false keel sections dry-fitted below. Each false keel section
was ca. 24 feet in length and 7 inches deep. I originally thought they were attached with staples,
but nails were more likely in this era. 

Gluing black velum to the false keel sections to simulate tarred flannel. 

Gluing the false keel to the keel assembly. Note the final shaping of the lower stem piece has not been completed. 

The 1836 plans indicate that false keel thinned as it ran forward; here I've mark off its run prior to final sanding.

The completed piece. Unfortunately the fluorescent lights I'm using don't do the richness
of the Swiss Pear justice  - indeed they make the wood look quite dry and pale when it actually is not. 

A view of the simple false keel scarphs near the centre of the keel. The false keel was designed to
tear away in the case of a grounding and was essential on bomb, merchant, and exploration ships.
Note that this is the port side of the keel (fore is on the left). 

Profile piece and station bulkheads cut from 1/4 inch plywood. 

Cutting the slots for the station bulkheads. 

Deburring with some wonderful scroll-saw sanding strips I purchased from Lee Valley.

The profile piece with all the bulkhead slots cut out. The fore and aft slots will be finished after the keel is glued
to the profile piece and the mast slots will be removed when the station bulkheads are all in place. 

The keel assembly and profile piece prior to gluing. 

The keel was pegged and glued to the profile section. 

The pegs continued up the stem. 

The keel assembly glued to the profile piece. Everything is square as far as I can tell - but the
clamping required was far too ugly to show here! The stern assembly will be fitted when the bolsters
for the propeller aperture are added and will need to be glued in the vertical position. 

Captain Crozier inspects the boxing.

"BUILDING HMS TERROR" IN CANADIAN GEOGRAPHIC MAGAZINE

The magazine with my own "wreckage" - of soon to be assembled parts. 

Canadian Geographic just released their special magazine devoted to the discovery of HMS "Erebus". It's a comprehensive issue filled with articles by members of the discovery team and some of the world's foremost Franklin researchers. It also includes some wonderful graphics, including never before seen photographs of the discovery.

I'm happy to report that Canadian Geographic asked to use my plans for their article on the ships, and if you buy the magazine you can see a custom version of HMS Terror's outboard profile, which is an updated version of a plan I produced many months ago.

They also interviewed me about the model itself and that Q and A can be seen on the digital content for the magazine here: http://www.canadiangeographic.ca/magazine/dec14/scale-model-hms-terror.asp

Special thanks to Jessica Finn, Photo Editor at Canadian Geographic, for her interest in my hobby!