Concept of Dashed Lines Indicating Hidden Geometry

[a1call]

Hi All,

I have looked for some time and can not find any indication that This drawing is not an original:

http://3.bp.blogspot.com/-C3zGet8n1Y...+Machine+2.gif

http://www.elixirofknowledge.com/201...oly-water.html

Is the concept of representing hidden geometry by dashed lines 2k years old?

Thanks in advance.

[grant hutchison]

Given that Hero's writings exist only in later translations, I think we can be sure it's not an original from Hero's time.
(Hero also wouldn't have used the Latin alphabet.)

Grant Hutchison

[a1call]

Given that Hero's writings exist only in later translations, I think we can be sure it's not an original from Hero's time.
(Hero also wouldn't have used the Latin alphabet.)

Grant Hutchison

Thank you for the deduction Grant.

Any estimates/guesstimates of the age of that drawing?

[grant hutchison]

It looks like an engraving to me. I'd guess it has been copied from a Renaissance translation, given that it appears to exist in a couple of different forms.
http://theincredibledaddy.com/wp-con...temple-urn.gif
http://3.bp.blogspot.com/-C3zGet8n1Y...+Machine+2.gif

Grant Hutchison

[01101001]

If you do a Google image search with the image cited, you will encounter other versions, less schematic, with shading, without the dotted line, that make me think they might be closer to the earliest drawings communicating the idea -- for instance, see: Tedium.co: A machine that gives you stuff

[a1call]

Thank you Grant.
Very much appreciate it.

[a1call]

If you do a Google image search with the image cited, you will encounter other versions, less schematic, with shading, without the dotted line, that make me think they might be closer to the earliest drawings communicating the idea -- for instance, see: Elixir of Knowledge: Ancient Coin-Operated Holy Water Dispensing Machine

Never seen that version before and I have searched before (image search).
Thank you.

[01101001]

Note: my link was accurate, but I used an errant description. I corrected my post: Tedium.co: A machine that gives you stuff

[grant hutchison]

Never seen that version before and I have searched before (image search).
Thank you.

Yes, that's the version that made me think of a Renaissance engraving.
Here is a late-Renaissance Italian translation (1592) of Hero's work, by Alessandro Giorgi of Urbino. Although the specific diagram isn't shown in the sample pages, the style is very similar.
The simplified version with the dashed lines would have been taken from the orginal some time later.

Grant Hutchison

[a1call]

Wow, you are good Grant.
The handles seem identical to one of the drawings (along with the wrong perspective) and there is a similar measured water dispenser with almost identical parts which seems to be based on manually pushing a lever rather than have it operated by a coin.
And as deduced, no dashed/dotted lines.
I am going to spend hours studying those drawings.
Thank you very much.

[profloater]

I may be way off on a tangent here but the practice of piercing through to copy drawings is ancient, producing a line of dots to guide the copier. The concept of dashed lines for hidden detail may be a separate but the line of dots might be an inspiration perhaps?

[a1call]

I may be way off on a tangent here but the practice of piercing through to copy drawings is ancient, producing a line of dots to guide the copier. The concept of dashed lines for hidden detail may be a separate but the line of dots might be an inspiration perhaps?

That is a very smart technique not many would think of. I am amazed by the lost knowledge and lifestyles. Measured dispensing of water is a feature absent from today's faucets. Some public faucets have a spring which immediately shut the valve without delay(or impractically short delays). There is hygiene advantages to not touching the faucet after washing is complete.

[profloater]

That is a very smart technique not many would think of. I am amazed by the lost knowledge and lifestyles. Measured dispensing of water is a feature absent from today's faucets. Some public faucets have a spring which immediately shut the valve without delay(or impractically short delays). There is hygiene advantages to not touching the faucet after washing is complete.

I think the Sistine chapel was done that way, and it was ancient then. It was even taught as a technique for design drawing on large sheets before the days of copiers and computers. Leather workers made patterns with piercing holes, it's hard to do any other way without modern tools like the pantograph, I don't know how old that is.

the modern controlled water is done by a proximity detector, no touch required, some arbitrary maximum programmed in.

[SkepticJ]

It's called pouncing, and is still commonly used in some applications.

[a1call]

It's called pouncing, and is still commonly used in some applications.

I have an exceptional memory. Before your post the conversation refreshed a very vague memory of simmering I have only seen once in my life decades ago when I was perhaps 4 years old. An architect family member had a tool shaped like a pen with a rolling gear at the end. i was going to Google to find it but thanks to your post, there it it is:
https://en.m.wikipedia.org/wiki/Pounce_(art)
I recall that it did not quite puncture the paper but left a dotted impression on both sheets.
ETA And now all this is revising me of another vague memory of sheets white paper with a transparent sheet glued over and along one long edge, where copying was done by putting originals on between and drawn on the transparent sheet.
No wonder most of my threads wonder far far away.

[Trebuchet]

Yes, that's the version that made me think of a Renaissance engraving.
Here is a late-Renaissance Italian translation (1592) of Hero's work, by Alessandro Giorgi of Urbino. Although the specific diagram isn't shown in the sample pages, the style is very similar.
The simplified version with the dashed lines would have been taken from the orginal some time later.

Grant Hutchison

Cool! Hero must have really loved syphons.

[a1call]

Well he seems to have been an all around genius. He seems to have invented the steam engine a few centuries before it was actually invented.
See if you can figure out how to calculate the area of any triangle using the length of its 3 sides (meaning you can't use trigonometry to use base times 1/2 the height). When (not if) you give up, Google Heron's Formula.