Comments on: Shape of a Zulu Shield?

Question: Shape of a Zulu Shield?

hellbient — Tue, 29 Mar 2005 08:26:25 -0800

Unsettled bar question: what is the shape of a Zulu Shield called?

Assume perfect symmetry. I thought it might be a Prolate spheroid, but that's 3D and looks as if it doesn't have the pointed ends needed to qualify.

By: Vidiot

Vidiot — Tue, 29 Mar 2005 08:42:17 -0800

Damn good question. The FOTW pages for Kenya and Swaziland don't give a formal name for the shape, unfortunately.

By: nebulawindphone

nebulawindphone — Tue, 29 Mar 2005 08:54:21 -0800

I would call it "almond-shaped." Dunno if there's a more formal term for it.

By: jessamyn

jessamyn — Tue, 29 Mar 2005 08:58:05 -0800

Symbols.com has some background on that shape and what it means symbol-wise. It may not have a geometric name.

The sign appears in the Egyptian hieroglyphic system. Drawn vertically, it much later became a symbol for Christ, vesica piscis, literally the air bladder of a fish. This sign is a symbol of virginity or purity. It often appears in a mandorla, i.e. surrounded by a radiating aurelia, or gloria, as in . The Cabbalistic mystics used to signify innocence.

By: Moondoggie

Moondoggie — Tue, 29 Mar 2005 09:02:16 -0800

To me, the shield looks more football-shaped (American football-shaped, that is). Looking for football shapes, I found two definitions on this page. One agrees with your initial assumption, a prolate spheroid, and the other goes with a more generic ellipsoid. I think the 3D part doesn't matter quite so much, as I believe the middle section curves outward, right?

By: Hildago

Hildago — Tue, 29 Mar 2005 09:05:35 -0800

If you met me on the street and showed me that picture, my snap response would be "leaf-shaped", but that's only because I think I've heard zulu shields described as leaf-shaped. If it was just a picture of a generic shape with those qualities, I would say "almond-shaped". For whatever that is worth to you.

By: odinsdream

odinsdream — Tue, 29 Mar 2005 09:05:58 -0800

The shape can be seen in one of the iterations of the Ellipse Negative Pedal Curve. I thought Lozenge best described it, but apparently that's technically not rounded, but more like a rhombus.

By: odinsdream

odinsdream — Tue, 29 Mar 2005 09:08:36 -0800

Ooh, even better.. Talbot's Curve.

By: kokogiak

kokogiak — Tue, 29 Mar 2005 09:10:10 -0800

I thought of it as a Venn Diagram Intersection (The shape made by two overlapping circles)

By: bachelor#3

bachelor#3 — Tue, 29 Mar 2005 09:11:19 -0800

I don't think Talbot's Curve is right, even though the shape hellbient is asking about is contained within it.

In jewelry, it'd be a marquise or a navette. In geometry, it might be a 2-sided Reuleaux Polygon, or digon. "Lenticular" (lens-shaped) might be an appropriate adjective.

Upon further snooping, it looks like it's just called a lens.

By: Moondoggie

Moondoggie — Tue, 29 Mar 2005 09:24:03 -0800

In line with kokogiak and jessamyn's suggestions, here's a page that says the shape caused by two overlapping circles is a called vesica. It's a little bit down the page - just search the page for "vesica" or "football."

You can take the boy out of West Texas, but you can't take the West Texas out of the boy...

By: kokogiak

kokogiak — Tue, 29 Mar 2005 09:27:59 -0800

From Bachelor#3's link, "It is also known as the fish bladder or vesica piscis... Renaissance artists frequently surrounded images of Jesus with the vesica piscis."

It's the Jesus Fish!

By: Moondoggie

Moondoggie — Tue, 29 Mar 2005 09:29:16 -0800

Running with Hidalgo's leaf idea, I stumbled across this page which calls the leaf of that shape elliptical. And I swear I found it looking for leaves and not footballs...

By: profwhat

profwhat — Tue, 29 Mar 2005 10:03:34 -0800

"All shield were made of cowhide, and were oval in shape, the big isihlangu type being slightly more pointed at either end than the umbumbuluzo." -- Ian Knight, Zulu, 1816-1906 (Warrior Series, No 14), ISBN 1855324741, page 20.

By: Rumple

Rumple — Tue, 29 Mar 2005 11:47:32 -0800

Like bachelor#3, I would say "lenticular" -- shaped like a biconvex lens. I use this term all the time to describe cross-section shapes and think it is pretty standard in the profession.

By: thomcatspike

thomcatspike — Tue, 29 Mar 2005 13:21:48 -0800

What would a Zulu call it?
Maybe you could translate its shape from that.

By: ikkyu2

ikkyu2 — Wed, 30 Mar 2005 04:06:45 -0800

I like 'lenticular' and 'amygdaloid'. But I'd probably call it a pointed oval, myself.