## 31 May 2016

### "Wide" vs. "long"

Marine scientists this week reported finding an immense sea sponge in a marine preserve near Hawaii.  They described it this way:
“It’s probably on the order of centuries to millennia old,” lead researcher Daniel Wagner told the Guardian. The sponge, the largest on record, is “about 12ft wide and 7ft long” he said, “so about the size of a minivan”.
I'll defer to the copyeditors who read this blog, but my assumption would be that the greater dimension would be referred to as the length and the shorter one as the width.  Unless a sponge has a front and a back...

1. I'm not aware of any reliable convention in this area. Choice of axis labels is arbitrary and equivalent.

Near the surface of bodies with strong gravity we appear to label the one parallel to the pull of gravity "height".

A hole has "depth" as does a cabinet, but those two axes are usually orthogonal to one another.

In one dimension objects usually have "lenght" or "displacement" and we often say that an ideal mathematical line has "no width".

But I don't think you could get a firm consensus on how to draw a 2x3 square.

2. Heh. Now square vs rectangle / quadrangle does have a reliable convention :) But my brain didn't honor it.

2. Sponges have an outside/inside and apex/base, but no front/back/side. Yes, for things that don't have a biological front, back, etc..., the longest axis parallel to the ground is typically called the length.

3. From looking at the article, I'm guessing this could be taken to mean "12 feet wide by 7 feet high", but it could also indicate two horizontal directions. I agree, the description is a bit screwy.

4. It could be how it was first approached and discovered. If you are scuba diving and come across something big and formless, the first dimension you are going to note is the span or width of this object. Then logically, the other dimension will be either depth or length.

5. I guess if it's broadly cylindrical then calling the diameter the width and the other dimension the length would make sense? Though if one end of that cylinder is the base I would have said "height".

6. It might be the way it 'grows' as is the case with timber. If you have a 12" wide plank of wood and you cut off a 2" piece, then in woodworking the piece would be considered to be 12" wide and 2" long. The length of wood is always the distance measured along the grain as opposed to across the grain.

1. That's an excellent point. Tx.