A clockwork orrery

Tick-tick, tick-tock, tick-tick. The clockwork inside the fat brass disk clicks as our guide turns the tiny brass handle of the Orrery.  It looks too small for his large gnarled hands, but he gently turns the handle and the delicate brass wires suspending the planets in their place begin to turn under the rhythm of the guide’s dancing Scottish burr.  Mercury is fastest, Venus tries to catch up, and Earth swats at its moon.  Mars marches onward at its own pace, while Jupiter issurrounded by a swarm of moons.  I had always thought Jupiter was the largest planet, but according to this Orrery, it is dwarfed by proud Saturn, who wears his rings like a torque of the ancient Celtic kings.  That makes six planets – at the beginning of the 19th century there were only seven.  The last was found by musician William Herschel: Georgium Sidus,  King George’s Star.  A smart move for Herschel who became the royal court astronomer, but a rather controversial move overall, leading the international community of astronomers to finally decide once and for all to name the planets after the Roman gods.

PHOTO/urban don

And it’s all run by clockwork.  The Orrery – that brass model of the sun-centered solar system – that we were looking at and assembling piece by piece was middling-quality according to our guide.  But I am blown away by the perfection of the way the model captures to rates of the planets’ movements.  The moons don’t move in this model, but in more extensive models they would have done, and it also would have been possible to replace the handle with clockwork so the Orrery was entirely automated.  The most expensive models would have used a candle for the sun, its flickering light illuminating the mechanics of solar and lunar eclipses.  On these models, the planets would rotate on their own axes, shadows casting the four seasons.  And it is all clockwork, every last move.

That is only one of the brass marvels housed at Oxford’s Museum of the History of Science. Globes of all sorts, some flat, some made entirely of brass rigs, some with clockwork hearts, others brightly coloured. Some of the globes are new, made by Oxford’s youth, their countries demarcated with photographs.  Electric lights glitter in the chandeliers once lit by oil lights and candles.  Glass bottles , elongated necks snaking weirdly about, have surfaces stained milky with residue of time and experimentation, the remains of Oxford’s first chemistry department.

The Museum of the History of Science, is a world of brass and clockwork, one where people debate if the planets are fixed in their position or are wandering stars with divine intelligences.  It is a world where the earth has been recently discovered – its position away from the center of the universe mystifying and radical.  It is a land where objects tell stories, stories about natural history, about a society in the midst of radical change, a land where Experimental Philosophy – later dubbed Sir Physics – became king.