To mark the centenary of the sinking of the Titanic on 12 April 1912, the National Maritime Museum put on an exhibition, entitled, Titanic Remembered, which highlighted some of the stories told by survivors of the disaster to Walter Lord, who wrote the book,  A Night to Remember on which the 1957 film of the same name was based.  When the exhibition closed at the end of September, there was a brief opportunity to research two of the Museum’s most emotionally evocative Titanic-related items before they are re-displayed in the ‘Voyagers’ gallery. Both are mechanical objects: an 18-carat gold pocket watch and a child’s musical pig.

Robert Douglas Norman and his 18-carat gold pocket watch (ZBA0004)

The owner of the watch, 27-year old Robert Douglas Norman, had joined the Titanic at Cherbourg, intending to visit his brother in Vancouver and from there continue to travel the world. As a male passenger, Norman’s chances of surviving the disaster were poor at best and his body was one of over 300 recovered by the cable ship, Mackay-Bennett. The watch was returned to his brother and passed down through the family until it was donated to the Museum in 1995.

The musical pig belonged to Edith Rosenbaum (1879–1975), who, like Norman, boarded the ship at Cherbourg. Edith, a 32-year old American, was a successful player in the fashion world and could afford to travel first-class. However, despite her professional success, her personal life was in pieces after she narrowly survived a road traffic accident, which claimed the life of her fiancé, Ludwig Loewe, in 1911.

The 'lucky pig' (ZBA2989)

Edith changed her surname to Russell in 1918, owing to political sensitivities following the First World War. In a televised interview, about 1970, she described how, when was asked to evacuate, she locked all 19 of her trunks before heading for the lifeboats. ‘I never would have left the ship,’  she recalled, ‘but a sailor came along and he said “say you;  you don’t want to be saved, well I’ll save your baby” and he grabbed this pig from under my arm and he tossed it in the lifeboat … when they threw that pig, I knew it was my mother calling me.’ (British Pathé 347801)

Edith followed the musical pig into the crowded Lifeboat 11 and, during the seven hours before being picked up by the passenger liner Carpathia, she comforted children on board with the tune, thought to be the Maxixe, from her lucky pig. Played by Theresa Thorne, Edith and the pig appear briefly in William MacQuitty’s film of Lord’s book, which shows her leaving her jewellery behind in favour of her lucky toy.

Edith Russell meets Theresa Thorne during filming of 'A Night to Remember'

The pig came to the Museum as part of the Lord-MacQuitty collection in 2003.

So did the pig really fly?

Well, dear reader, I am afraid that I may have over-egged the flying bit; it was more like travelling at sensible speed up the M1 in a van en route to the Nikon Metrology factory in Hertfordshire. But it was to be an extraordinary day, and as is the case with extraordinary days, relativity comes into effect and they are over all too soon. Even if the pig didn’t literally fly the time certainly did!

Nikon Metrology produces high resolution X-ray equipment that is normally used for doing failure analysis on, and checking the internal quality and precision of components such as electronic chips, automotive parts and aircraft turbine blades: objects with complex internal structure that have to be made exactly to specification. The systems can also be used to examine material properties in materials research, soil science and geology. We were met by computed tomography (CT) specialist, Andrew Ramsey, who is incidentally the first person in over 2000 years to have seen inside the Antikythera Mechanism, an ancient Greek astronomical calculator, and had very kindly agreed to set a couple of days aside to examine our two Titanic relics using state-of-the-art CT scanning equipment.

A common factor of both of these objects is that neither can be opened without causing irreparable damage. The pig’s body is constructed from organic material, wood and papier maché are identifiable where the legs have broken and the outermost layer is of pig skin moulded around the carcass and pinned in places. Externally there is no evidence to suggest that the toy was designed so that the musical movement could be extracted for servicing and also no clue as to what sort of movement it contains. The watch, with its rust-stained glass and dial, is an extraordinarily poignant object with the hands – which read 3.07 – apparently frozen at the time of entering the water. Because of the watch’s condition and the nature of its history, we could never justify opening its case, let alone dismantling the movement.

Ready for the first scan, the watch safe inside its travel box on the turntable and the lucky pig packed in plastazote and acid-free tissue

We hope that the CT scan will eventually help us to answer the big question surrounding the watch, which is raised by the discrepancy between the time it shows and the officially recorded time of sinking of 2.20 a.m. It has always been believed that watch stopped when it entered the sea and that the time disparity highlights the issue of the changing local time as one travels westwards. Put another way, passengers would probably have had to adjust their watches daily to keep in step with local time, and so Norman would have been due to set his back the following day. But, of course, there was always a slim chance that the watch had stopped some time before entering the water and we hope the CT scan will help clarify this. We also hoped to learn what sort of watch movement was hidden within the case and who might have made it.

When it comes to x-rays, gold has similar properties to lead in that it tends to act as a shield. For this reason the watch went into the scanner first, in case we needed to use a more powerful machine. In this day and age, the x-ray image is not an unusual phenomenon, but the first view of its inside was thrilling: despite the 18-carat gold inner case back, known as the cuvette, we were going to get a really good look.

Each scan took just under half an hour to complete and, during scanning, the object is rotated through 360 degrees. The data is sent to a computer and converted into tiny building blocks called voxels, each representing a cube measuring 32.6 µm across (approximately 0.03mm) which are then put together to create the 3-D model. Once created it is possible to slice through any specified area to have a look inside the object.

One of the first dramatic shots of the mechanism shows it to be an English fusee watch with full-plate movement and bi-metallic balance.

A first view of the watch movement through the cuvette and cap

A maker/retailer’s signature can just be made out but the gold has rather fogged the image. Because of this lack of clarity there is still a lot of sifting to do through the vast quantities of data, approximately 80 gigabytes in total, before we can be certain that we have the answers we are looking for.

By contrast, the lucky pig was far more scanner-friendly and we were very quickly able to see some spectacular results. It required two scans, the first to pick out the details of the main body and a second to obtain good images of the musical movement. To scan the movement, the lower energy radiation had to be filtered out and this is achieved by placing a small copper sheet in the path of the x-rays before they met the object.

The 3-D model of the pig assembled and ready for dissection

Dissecting the digital model down the middle gave us our first view of the pig’s interior and, as can be seen, it is made from moulded papier maché, with a transversely mounted wood soundboard to which the musical movement is mounted.

The rendered dissection showing the inner surface of the carcass, perhaps reminiscent of Damien Hirst’s ‘Mother and Child Divided’

From this scan we learn that the tail is simply a knotted piece of vellum that was never connected to the music box. Prior to scanning it seemed likely that this was spring-driven and activated by pulling the tail but the scans show us that it was a hand-powered type of movement, known as a manivelle (French for crank-handle). By slicing across the width of the model the cause of a rattling noise was identified as a hairpin, probably used in attempt to reconnect to the music box after the crank had broken away. The S-shaped object in the centre appears to be the original crank-handle and tail. Detailed examination of this object shows it to be a skin-covered metal tube, which is an unexpected and very exciting find, perhaps a case for key-hole surgery…

The model bisected horizontally, showing the shell construction of the carcass and the loose hairpin and what is possibly the original tail/crank-handle. The bright spots down the belly centreline are the pins securing the outer skin

The second scan of the lucky pig produced some brilliant images of the musical movement, showing it is quite simple in construction. It has a toothed wheel attached to the pin barrel, which is driven by a worm gear on the end of the crank shaft. The comb is marked with a distinctive star logo, which may in due course help us identify the maker.

Two views of the musical movement

The movement showing the star logo, by the screw on the near corner of the comb

What has been shown here is only the beginning of the study; these 3-D models provide invaluable information that will assist with our curatorial questions as well as the long-term care and conservation of these extraordinary objects.

It is unlikely that anyone came into work feeling more refreshed than usual following the insertion of an extra second into Saturday 30 June. While this event did not affect our body clocks, it did have an effect on the National Maritime Museum’s collection. At the Royal Observatory two clocks, in particular, needed adjustment: the Shepherd gate clock (ZAA0533) and the Hewlett Packard atomic clock (ZBA2599).

The Shepherd gate clock was installed at the Observatory in 1852 under the direction of the seventh Astronomer Royal, George Biddell Airy, and is named after its maker, Charles Shepherd. The clock’s installation marks the beginning of the Royal Observatory’s role as a provider of accurate time for the nation. Today it can be relied upon to show Greenwich Mean Time (GMT) accurate to half a second. The second clock was originally used at the National Physical Laboratory in the 1990s for its contribution to the international time-scale, known as Coordinated Universal Time (UTC).

Why do we need a leap second?

Believe it or not, the Earth is not as reliable a timekeeper as our atomic clock and the leap second is a fine-tuning that keeps UTC synchronized with the motion of the Earth. The speed of our planet’s rotation is variable for a number of reasons. Generally speaking, the Earth’s rotation is slowing down because the Moon is gradually moving away from us: there is no need for alarm as it is only moving away at about the same speed our fingernails grow, but as it does so its gravitational influence is lessened. This and other unpredictable influences, such as seismic activity, are monitored by the International Earth Rotation and Reference Systems Service (IERS), who decide whether or not a leap second is necessary.

The leap second has caused us to adjust the two clocks already mentioned and make a basic equivalent calculation when comparing the rates of precision pendulum clocks against a radio-controlled clock. But for those responsible for managing computer networks that handle large volumes of digital traffic the leap second poses a tricky problem. Networks depend on accurate timekeeping: every data transfer is time-stamped and any data logged during the leap second will be outside of the computer’s logic. This could potentially cause the system to fail. Indeed, there are reports indicating that some systems did stop working after last Saturday’s leap second and, as a result, some popular websites were inaccessible. Among various ways of overcoming this problem, there is one that bears an interesting parallel to operational principles used by Airy in the mid-1800s. Google, in preparation for the 2005 leap second, opted to add it, in advance and over a set period across their system, in tiny increments that did not upset communication with any other systems that they were connected to. They named their method the ‘leap smear’.

The same principle was applied to the system that drove the gate clock at the Royal Observatory. Most people do not realize that this is a slave clock, not a timekeeper in its own right: it was originally one of several slave dials on the site, all of which followed the instruction of Shepherd’s master clock (ZAA0531). The beauty of Shepherd’s master clock was not that it was an exceptional timekeeper but that it could be corrected electrically by means of electro-magnetic adjusters working on the pendulum. Small and precise adjustments to the hands could be made by causing the pendulum to move faster or slower over a fixed period of time; and because the master clock was continuously sending out pulses to all of the slave clocks, the slaves were automatically corrected. Today, the gate clock is driven by a radio-controlled Quartz clock and the hands are corrected manually.

Of course, the leap second was unheard of in Airy’s time; the first leap second was implemented in 1972 and, since then, a total of 35 have been inserted into UTC. The IERS gives six months’ notice of forthcoming leap seconds in their Bulletin C, so we will have at least another year before we can look forward to a ‘long’ weekend like that of 30 June – 1 July 2012.

Conserving the H3 Timekeeper from Royal Observatory Greenwich on Vimeo.

This second installment reveals how the timekeeper is being dismantled and recorded.

Conserving the H3 Timekeeper from Royal Observatory Greenwich on Vimeo.

A short film documenting the dismantling of John Harrison‘s third marine timekeeper H3. It has been removed from display for cleaning and research for a new chronometer catalogue. It will be back on display in April 2011.

Harrison’s second timekeeper, H2, has been in the horology conservation workshop at the Royal Observatory undergoing research for quite a few weeks now and its study is proving most interesting. The complete measurement of all the parts has now been completed and photography is well under way.
West Dean College have been extremely helpful in making their XRF metals analysis equipment available to us, and the Clock Course Tutor, my old colleague Matthew Read, came up to Greenwich for the day to help with tests on a number of parts of H2 which appear to employ unusual alloys.
Some years ago the V&A kindly carried out XRF analysis on some of the parts of H3 and we discovered that Harrison employed various types of tin-bronze, principally in place of steel, which naturally would have been inclined to rust in a marine environment. It is reassuring to find after this recent analysis that those results were confirmed by the same alloys, chiefly a low tin-bronze where good tensile strength is required, and a very high tin-bronze where high compression strength is needed (such as in the anti-friction segments supporting the balances).
As is now well known, these timekeepers run without lubrication, and I was most interested to see if H2, like H1, has survived in good order after 50 years of constant running. I calculated, for example, that the balances, which each weigh over 8lbs, will have rolled on their bronze segments over one and a half billion times! Well, I was astonished to find that, after all those years, the bearings are simply unmarked. I am sure the balances could continue for several more billion oscillations without harm coming to them.
Delays over the photography have meant that the timekeeper’s return to the gallery has also been delayed, but reassembly is now about to start. Further updates will follow before the timekeeper returns to exhibition in the Longitude Gallery, now estimated to be sometime in early August.