The Attraction of Mountains, 1774 (The Schiehallion Experiment)

In November last year, Dr. Liz Auty, John Muir Trust’s East Schiehallion Property Manager, presented a comprehensive talk to our Society on the Reverend Nevil Maskelyne’s 1774 expedition to Schiehallion, and the organisation and the people behind his experiment to ‘weigh’ the mountain and the world.

In the poem below, Jon Plunkett, a well-known poet resident in Aberfeldy, creates an evocative picture of the mountain, Maskelyne’s expedition and his experiment.

1 – Theory

An apple tree among the stars,

and from it a single apple falls.

It spins through the spheres,

draws a line straight and true.

A straight line, a true line, until –

from the planet’s rippled crust

a mountain rises, exerts a pull –

enough to sway that falling fruit.

2 – Mountain

In the heart of Scotland

a mountain of symmetry and bulk.

A shark’s fin of earth and stone

in and out of cloud, in and out of cloud

soaked and soaked again.

A place of ancient spirits, and new spirits –

illicit stills nestled by the burns

on this rock-crowned king of hills.

3- Experiment

The measurements are minute,

fractions of fractions taken from the space

between a star-line straight and true,

and a plumb-line’s slim deflection –

the most subtle bend of gravity,

the tiniest sway of cosmic force,

and just enough to weigh the world.

4 – Men

They are small, there on the hardship of the hill,

five hundred and fifty metres up

in bothies to house them and their tools.

Small, there on the flanks of a spinning planet.

And from this tangle of human complexities,

sharing small confines for weeks,

emerged – miraculously –

the measurements needed.

5- Results

Three hundred and thirty-seven

observations of seventy-six stars.

Several hundred triangles

in various orientations.

Innumerable micro-measurements

of a plumb-line pulled.

From the maze of calculations

two things: the mountain

depicted in concentric circles,

and the approximate weight

of the world.

6- Conclusion

Take a clear Schiehallion night

under an apple tree of stars.

Climb until you reach the smallest contour.

Climb until there is no more hill to climb

and there look up and know –

the world weighs more than first was thought

and this mountain will attract

always.

Jon Plunkett

If you are interested in the talk which Liz presented to our Society, please follow the link below to our subsequent blog where you will find a link to the video of her talk: https://breadalbane-heritage.org.uk/2022/08/21/the-attraction-of-mountains/

Following on from the talk and as one of of our summer excursions this year, on the 8th of June Liz led a group of BHS members to explore the lower slopes of the John Muir Trust’s Eastern Schiehallion site looking at some of the archaeology, social history, and the flora and fauna of this area. You can find the details of this summer excursion by following the link to our subsequent blog: https://breadalbane-heritage.org.uk/2022/07/27/bhs-visit-to-east-schiehallion/