Lightnews — Scholar-powered news

LightNews

James Taite

@jamestaite.bsky.social

2.2K followers 1.9K following 1.2K posts

Stonemason in Ottawa, Canada

Posts Media Videos Starter Packs

Reposted by James Taite

Bruno Tonelli @brunotonelli.bsky.social · 17h

Rotonda di San Lorenzo
Mantova

Reposted by James Taite

Bruno Tonelli @brunotonelli.bsky.social · 17h

Leon Battista Alberti
Sant'Andrea
Mantova

Reposted by James Taite

Bruno Tonelli @brunotonelli.bsky.social · 17h

Leon Battista Alberti
Sant'Andrea
Mantova

Reposted by James Taite

👁🌻🦊⚙️⚓ Bob, Engineer, Pusher of Paper @navmecheng.bsky.social · 1d

> It is 2025 BC. I am a soldier from one of the outlying provinces called to defend the pyramid in Memphis

> It is 2025 AD. I am a soldier from one of the outlying provinces called to defend the pyramid in Memphis

Soldiers at the Bass Pro Shops pyramid in Memphis, TN.

Reposted by James Taite

Bill Kristol @billkristolbulwark.bsky.social · 23h

Pope Leo quotes Hannah Arendt:

“The ideal subject of totalitarian rule is not the convinced Nazi or the convinced Communist, but people for whom the distinction between fact and fiction and the distinction between true and false no longer exist."

www.cbsnews.com/chicago/news...

Pope Leo calls for news agencies to stand as bulwark against "post-truths," lies and manipulation

Pope Leo XIV has encouraged international news agencies to stand firm as a bulwark against the "ancient art of lying" and manipulation.

www.cbsnews.com

James Taite @jamestaite.bsky.social · 22h

art can only do so much! sometimes you need an engineer!

James Taite @jamestaite.bsky.social · 23h

…The hidden key. Hide the radiating joints inside the stone and make the visible perps vertical.

Artful ruses.

page from ‘Modern Practical Masonry’, E.G. Warland, 1929 illustrating the use of a hidden or secret key arch

Hidden key on limestone voussoir; photo mine

Hidden key on limestone voussoir; photo mine

James Taite @jamestaite.bsky.social · 23h

But if you didn’t want radial joints? If you didn’t want this arch to look like an arch? If you were so committed to the idea of trabeation that the hint of an arch, even one with a flat soffit, was unthinkable? Then there was another way, a secret way…

Covent Garden market, London; monolithic Doric columns carrying a horizontal entablature & balustrade; photo mine

closer view of Covent Garden Market colonnade; joints in the soffit between points of support are vertical, not radiating from a centre; photo mine

James Taite @jamestaite.bsky.social · 23h

Even with a horizontal intrados the flat arch still functions as an arch, though maybe less reliably, less faithfully. More likely to fail.

Province House, Charlottetown; photo 1939, Toronto Public Library, Toronto Star archives

neoclassical tetrastyle portico of widely spaced Ionic columns; the central opening is spanned by a flat arch that has visibly dropped

James Taite @jamestaite.bsky.social · 23h

The innovation of the flat arch was to retain those centred joints while dispensing with the circumferential intrados. They have no (or miniscule) rise, but the joints still need to be radial. The secret to their success lies in this stereotomy.

window topped by a flat arch; the Gibbs surround of alternating profiled and block voussoirs emphasizing the radiating nature of the joints; photo mine

James Taite @jamestaite.bsky.social · 23h

…but the principle is the same: for an arch to function as an arch, joints radiate. It’s this geometry—the defining centre—that translates the vertical loads imposed on the arch by gravity into lateral thrust, diverting them around the opening.

St. Mary Woolnoth, London
pair of half-round arches in deeply channelled rusticated stone, emphasizing the radial pattern of joints between voussoirs; photo mine

James Taite @jamestaite.bsky.social · 23h

Arches want a rise, arches want to spring. A half-round or segmental arch has a centre that both describes the curve of the intrados and locates the point from which the joints between voussoirs radiate. Other arches have more complicated geometry, and maybe multiple centres…

James Taite @jamestaite.bsky.social · 23h

At their most basic, arches are defined by two dimensions: span and rise. First is the distance between points of support. Second is the height of the arch from its springing point, where the vertical jamb of the opening curves into the non-vertical soffit—or intrados—of the arch.

page from ‘A Treatise on Masonry Construction’, 1920, Ira Osborn Baker, showing the parts of an arch

James Taite @jamestaite.bsky.social · 23h

But the oldest and simplest of these sleights of hand is an adaptation of those arcuated forms that come naturally to stone: the flat arch.

Anticipating the stone to fail and crack into pieces you can crack them before the cruel world does. Crack them where you want them to crack.

window in a pecked, coursed limestone wall topped with flat arch; photo mine

James Taite @jamestaite.bsky.social · 23h

Likewise the post-tensioned stonework of outfits like www.thestonemasonrycompany.co.uk, turning odd bits of stone into structural beams and slabs by threading them on steel rod. Cinched tight, the material is put into compression and made able to span amazing distances.

blocks of stone assembled into uprights and lintels, post-tensioned, by The Stonemasonry Company; photo from twitter account @stonemasonryco

James Taite @jamestaite.bsky.social · 23h

So for millennia builders’ ingenuity has been tested, devising ways to give the look of trabeated stonework—to make flat soffits—without having to build trabeated stonework. Artful ruses. Like the ingenious fuckery of 19th & 20th c classicism, hanging stone from steel or concrete structure.

page from Modern Practical Masonry, E.G. Warland, 1929 illustrating methods to hang stone cladding on steel & concrete structures

Union Station, Ottawa, 1909-10, Library and Archives Canada.
neoclassical building under construction, with prominent stone columns; steel structure visible behind

James Taite @jamestaite.bsky.social · 23h

As a structural system, as a method for enclosing space, it’s kinda shit; those soffits are in tension, a force resisted poorly by stone. You either limit spans to the capacity of the material, or it cracks and fails.

looking at underside of Maltese limestone planks spanning approx. 3' between arches. The stone has cracked and been reinforced with steel bars; photo mine

James Taite @jamestaite.bsky.social · 23h

What’s the obsession with level stone lintels on plumb stone columns? The lithified x and y of Euclidian space? Humanity’s post-Ardipithecine upright posture? Cosmic axes of calumet-smoke rising against the flat featureless terrifying extension of the horizon?

British Museum, London. Ionic columns carry a heavy horizontal entablature; photo mine

James Taite @jamestaite.bsky.social · 23h

For thousands of years we’ve been building with trabeated stone. For thousands of years it’s been chewed at, chased to abstraction. Repeatedly exhumed and revived, even after Roman concrete, even after Gothic vaults, after Rundbogenstil and Candela’s shells. Keeps coming back from the dead.

a 🧵:

ruins of the Temple of Poseidon at Sounion. Doric columns carrying stone lintels against a blue sky; photo mine

15 Clerkenwell Close, London, by Groupwork Architects, @amintaha. building with gridded exoskeleton of stone columns and lintels, variously saw-cut or quarry-faced; photo mine

James Taite @jamestaite.bsky.social · 1d

Thanks for taking the time to read it Marta!

James Taite @jamestaite.bsky.social · 1d

coo roo coo coo ca coo coo coo

James Taite @jamestaite.bsky.social · 1d

peak hoser

Reposted by James Taite

Michael Burchert @michaelburchert.bsky.social · 27d

Load bearing clay masonry in Augsburg.
We can do 4 storeys since last year in D. (Again; this one of the defining building technologies of mankind.)

Mudbricks basically.
Fired bricks only where necessary.
What is not there cannot emit CO2.

Foto: ZRS Ingenieure

www.instagram.com/p/DOfstT0iJ2...

Construction site visit on a multi storey clay masonry site. Ring beam on top. The whole site is covered with a scaffolding and roof to prevent moisture.

Reposted by James Taite

Nora Reed (they/them ze/hir) @nora.zone · 2d

cry havoc and let slip the frogs of war

James Taite @jamestaite.bsky.social · 1d

And the flip-side to the lintel that wants to pass as an arch is the hidden key. Where the limitations of the stone call for an arch, but the appearance of an arch is unwanted, we get an arch in denial, with flat soffit and apparently vertical—not radial—joints.