On 12/28/2023 12:05 PM, Leon Fisk wrote:
>
> See the Taylor Hydraulic Air Compressor for some interesting reading. A
> patent with some info and related pointers here:
>
> https://patents.google.com/patent/US4797563A/en
>
> and an old report:
>
> https://archive.org/details/IllustratedDescriptionOfTheTaylorHydraulicAirCompressorAndTransmission
>

That's SO neat! So out-of-the-box! An air compressor with no rotating
parts.

One of the best features: the air pressure is independent of the head of
the water power source. The air pressure is determined by the depth of
shaft that the compressor is housed in. The head determines the flow &
power, but not the pressure.

On Fri, 29 Dec 2023 10:27:20 -0500
BobEngelhardt <BobEngelhardt@comcast.net> wrote:

>That's SO neat! So out-of-the-box! An air compressor with no rotating
>parts.
>
>One of the best features: the air pressure is independent of the head of
>the water power source. The air pressure is determined by the depth of
>shaft that the compressor is housed in. The head determines the flow &
>power, but not the pressure.

I put another small doc here (5 images) about the Victoria Mine
installation. It's from scraps I picked up from a friend in the area:

https://postimg.cc/gallery/Q3mhSXK

--
Leon Fisk
Grand Rapids MI

"BobEngelhardt" wrote in message news:ummogp$sclg$1@dont-email.me...

That's SO neat! So out-of-the-box! An air compressor with no rotating
parts.

-----------------------------

The same principle creates vacuum.
https://www.flinnsci.com/products/apparatus/laboratory-equipment/water-aspirators/

Before water use appeared on sewage bills it was a cheap, zero maintenance
way to evaporate water or solvent from a solution without risking
contamination or condensation damage to a mechanical vacuum pump.

A jet of steam sucking in water can raise the water's velocity and kinetic
energy high enough to force open a check valve into the boiler that provided
the steam, thus it's a feed pump with no moving parts except the control
valves.
https://en.wikipedia.org/wiki/Injector

On steam locomotives it was usually more practical to use a vertical jet of
cylinder exhaust steam at the base of the stack to increase the draft
through the firebox than to condense and reuse it, since smokestacks had to
be short enough to clear bridges and tunnels and air-cooled condensers were
bulky and fragile. This is why the stack puffed. The exception was trains
passing through large deserts.

https://en.wikipedia.org/wiki/Henri_Giffard
The Wright's achievement was powered flight on wings, manned ballooning
began in 1783.

On Fri, 29 Dec 2023 06:54:15 +0000, Richard Smith <null@void.com>
wrote:

>Gerry <geraldrmiller@yahoo.ca> writes:
>
>>> ...
>>>
>>>> From my experience about sixty years ago, the crew opperating a
>>>> "Delmag" pile driver, wear black (beige when new) coverals!
>>>
>>>From grease lubrication and from part-burned fuel?
>>>
>
>> Black rain!
>
>The exhaust has thick liquidy raining-down hydrocarbon residues?
Goo description.

On 12/29/2023 11:15 AM, Leon Fisk wrote:
> I put another small doc here (5 images) about the Victoria Mine
> installation. It's from scraps I picked up from a friend in the area:
>
> https://postimg.cc/gallery/Q3mhSXK
>

Thanks. It was interesting, but missing some referenced figures. So I
went looking for the article. I found it here:
https://archive.org/details/miningscientific93sanfuoft/page/204/mode/2up?view=theater

But it is what you posted - i.e. missing some figures. Oh well.

On 17/12/2023 23:24, Bob La Londe wrote:
[...]
>
> I think urea is the same as ammonium nitrate.

Urea itself is not explosive, and is seldom used in explosives, though
it is sometimes added in small proportions to ANFO to prevent noxious
gases when eg pyrite is present.

Urea nitrate is sometimes used in home made explosives, but it is not
used in any civil explosives I know of, or for blasting purposes -
that's mostly the province of ANFO and water gels, with gelignites and
dynamites occasionally used on smaller scales and for demolition work.

Water gels and emulsion explosives are typically mixed on-site from
ammonium nitrate solutions plus fuels. They are usually not
cap-sensitive, though cap-sensitive ones do exist, and need a booster
explosive charge to detonate. The non-cap-sensitive ones are easier to
transport.

ANFO is also often made on site. Ammonium nitrate prills come in two
types, in one the prills are carefully engineered so that they will
absorb exactly the right amount of fuel oil if they are to be used in
ANFO explosives, and in the other they are engineered so they won't
absorb fuel oil if the AN is to be used as fertiliser.

Sorry, I don't have any practical experience in blasting tunnels. You do
usually need higher velocity explosives like dynamite or gelignite for
hard rocks though.

Peter Fairbrother

Peter Fairbrother <peter@tsto.co.uk> writes:

> On 17/12/2023 23:24, Bob La Londe wrote:
> [...]
>>
>> I think urea is the same as ammonium nitrate.
>
> Urea itself is not explosive, and is seldom used in explosives, though
> it is sometimes added in small proportions to ANFO to prevent noxious
> gases when eg pyrite is present.
>
> Urea nitrate is sometimes used in home made explosives, but it is not
> used in any civil explosives I know of, or for blasting purposes -
> that's mostly the province of ANFO and water gels, with gelignites and
> dynamites occasionally used on smaller scales and for demolition work.
>
> Water gels and emulsion explosives are typically mixed on-site from
> ammonium nitrate solutions plus fuels. They are usually not
> cap-sensitive, though cap-sensitive ones do exist, and need a booster
> explosive charge to detonate. The non-cap-sensitive ones are easier to
> transport.
>
> ANFO is also often made on site. Ammonium nitrate prills come in two
> types, in one the prills are carefully engineered so that they will
> absorb exactly the right amount of fuel oil if they are to be used in
> ANFO explosives, and in the other they are engineered so they won't
> absorb fuel oil if the AN is to be used as fertiliser.
>
>
> Sorry, I don't have any practical experience in blasting tunnels. You
> do usually need higher velocity explosives like dynamite or gelignite
> for hard rocks though.
>
>
> Peter Fairbrother

Thanks for that.
Since I posted this question I have learned a lot.

The "traditional" blasting medium used in Cornwall was gelignite.
I've had comment that cost would make you have second thoughts about
doing that to conform with tradition.
Brings ANFO to the fore now.
I've read about "emulsion". Seems is "the business" when you have a
big tanker driving around pouring into many big blasting holes.
"per-unit" cost very favourable - but the costs of maintaining a
storage of "ANBI", pumps to safely handle ANBI, etc. - the set-up and
maintenance costs - might have you looking at ANFO (?)

I have a lot more learning to do.
Couple of articles recommended here which I am reading.
Wanted to post something along the lines of "Wow!" in that what was
unintelligible before now in the main makes sense.
Will continue to read and learn in other ways then report back.

The granite I met here is so hard that a powerful rock-drill
(percussion plus rotation) could not drill with a four-cutting-tips
cutter - had to revert back to a carbide-tipped chisel-edge drill.

Implies that need a goodly blasting medium.

Anyway, hopefully will be back here soon.

Rich S

"Richard Smith" wrote in message news:lyfrzjffmm.fsf@void.com...

The granite I met here is so hard that a powerful rock-drill
(percussion plus rotation) could not drill with a four-cutting-tips
cutter - had to revert back to a carbide-tipped chisel-edge drill.

Implies that need a goodly blasting medium.

Anyway, hopefully will be back here soon.

Rich S
------------------------
With my drill NH granite cuts faster by starting with a 1/2" bit. "Fast" is
relative, at least I can see it move.

By Hiram Maxim's brother:
https://www.gutenberg.org/files/46039/46039-h/46039-h.htm

https://www.gutenberg.org/files/65791/65791-h/65791-h.htm

On Sat, 30 Dec 2023 15:56:36 -0500
BobEngelhardt <BobEngelhardt@comcast.net> wrote:

<snip>
>Thanks. It was interesting, but missing some referenced figures. So I
>went looking for the article. I found it here:
>https://archive.org/details/miningscientific93sanfuoft/page/204/mode/2up?view=theater
>
>But it is what you posted - i.e. missing some figures. Oh well.

I had access to two "scrap books" from the Victoria Mine for a
short period a long time ago and scanned them. It had all sorts of
compiled news articles, ephemera concerning the mine. They were all
clippings in various shapes and not always easy to decipher how they
originally went together. I likely have the "missing" items just didn't
know where they belonged🤷

I used to vacation in the area and collected several more recent books
on the subject along with other odds & ends. It was a long time ago...

--
Leon Fisk
Grand Rapids MI

On 30/12/2023 23:13, Richard Smith wrote:
> Peter Fairbrother <peter@tsto.co.uk> writes:
[...]
>> Urea nitrate is sometimes used in home made explosives, but it is not
>> used in any civil explosives I know of, or for blasting purposes -
>> that's mostly the province of ANFO and water gels, with gelignites and
>> dynamites occasionally used on smaller scales and for demolition work.
>>
>> Water gels and emulsion explosives are typically mixed on-site from
>> ammonium nitrate solutions plus fuels. They are usually not
>> cap-sensitive, though cap-sensitive ones do exist, and need a booster
>> explosive charge to detonate. The non-cap-sensitive ones are easier to
>> transport.
>>
>> ANFO is also often made on site. Ammonium nitrate prills come in two
>> types, in one the prills are carefully engineered so that they will
>> absorb exactly the right amount of fuel oil if they are to be used in
>> ANFO explosives, and in the other they are engineered so they won't
>> absorb fuel oil if the AN is to be used as fertiliser.
>>
>>
>> Sorry, I don't have any practical experience in blasting tunnels. You
>> do usually need higher velocity explosives like dynamite or gelignite
>> for hard rocks though.
>>
>>
>> Peter Fairbrother
>
> Thanks for that.
> Since I posted this question I have learned a lot.
>
> The "traditional" blasting medium used in Cornwall was gelignite.
> I've had comment that cost would make you have second thoughts about
> doing that to conform with tradition.

Yes, it is more expensive. As is NG-dynamite. However they are about
twice as powerful as ANFO, so you need less.

> Brings ANFO to the fore now.
> I've read about "emulsion". Seems is "the business" when you have a
> big tanker driving around pouring into many big blasting holes.
> "per-unit" cost very favourable - but the costs of maintaining a
> storage of "ANBI", pumps to safely handle ANBI, etc. - the set-up and
> maintenance costs - might have you looking at ANFO (?)

I'm unsure whether the AN used in ANFO is itself an ANBI - if AN is
prilled for explosives purposes it might well be. Or perhaps it is
controlled under one of the many AN control orders, which I have only a
passing familiarity with.

However there is another problem or three with ANFOs, AN water gels and
emulsions - they need bigger holes than NG-dynamites or gelignites, as
they will not explode properly when the diameter of the hole is small.

In practice, combined with the fact that they are only about half as
powerful, you end up using a lot more. Which means a lot more nasty
gases to get out of your tunnel.

Second, they really need boosters. There are cap-sensitive gels and
emulsions, but then you are getting into the same legal hassles as the
higher velocity explosives - plus you need different certificates and
licenses for the boosters. Some people use detcord as a booster, but the
same requirement for an explosives certificate etc applies (in the UK).

Third, and perhaps most important, especially when used for tunnels in
hard rock, they aren't really brisant enough to cope with hard granite.
The NG-based (or NC-based) high velocity explosives produce shock waves
which will fracture granite, but the lower velocity of detonation of the
AN-based explosives give more of a hard push than a breaking shock.

> The granite I met here is so hard that a powerful rock-drill
> (percussion plus rotation) could not drill with a four-cutting-tips
> cutter - had to revert back to a carbide-tipped chisel-edge drill.
>
> Implies that need a goodly blasting medium.

Indeed. Gelignite, or a NG-dynamite, seems called for.

Also, for a a small tunnel, AN-based explosives are generally less
useful - though they do make small diameter cap-sensitive AN emulsions,
AN-based explosives are generally better for larger charges.

You didn't say how long the tunnel is, but unless it is very long
jelly/NG might even be cheaper. It will certainly be more practical and
need less drilling.

BTW, Cranfield sometimes do a short course on mining explosives.

Peter Fairbrother

Peter Fairbrother <peter@tsto.co.uk> writes:

> On 30/12/2023 23:13, Richard Smith wrote:
>> Peter Fairbrother <peter@tsto.co.uk> writes:
> [...]
>>> Urea nitrate is sometimes used in home made explosives, but it is not
>>> used in any civil explosives I know of, or for blasting purposes -
>>> that's mostly the province of ANFO and water gels, with gelignites and
>>> dynamites occasionally used on smaller scales and for demolition work.
>>>
>>> Water gels and emulsion explosives are typically mixed on-site from
>>> ammonium nitrate solutions plus fuels. They are usually not
>>> cap-sensitive, though cap-sensitive ones do exist, and need a booster
>>> explosive charge to detonate. The non-cap-sensitive ones are easier to
>>> transport.
>>>
>>> ANFO is also often made on site. Ammonium nitrate prills come in two
>>> types, in one the prills are carefully engineered so that they will
>>> absorb exactly the right amount of fuel oil if they are to be used in
>>> ANFO explosives, and in the other they are engineered so they won't
>>> absorb fuel oil if the AN is to be used as fertiliser.
>>>
>>>
>>> Sorry, I don't have any practical experience in blasting tunnels. You
>>> do usually need higher velocity explosives like dynamite or gelignite
>>> for hard rocks though.
>>>
>>>
>>> Peter Fairbrother
>>
>> Thanks for that.
>> Since I posted this question I have learned a lot.
>>
>> The "traditional" blasting medium used in Cornwall was gelignite.
>> I've had comment that cost would make you have second thoughts about
>> doing that to conform with tradition.
>
> Yes, it is more expensive. As is NG-dynamite. However they are about
> twice as powerful as ANFO, so you need less.
>
>> Brings ANFO to the fore now.
>> I've read about "emulsion". Seems is "the business" when you have a
>> big tanker driving around pouring into many big blasting holes.
>> "per-unit" cost very favourable - but the costs of maintaining a
>> storage of "ANBI", pumps to safely handle ANBI, etc. - the set-up and
>> maintenance costs - might have you looking at ANFO (?)
>
> I'm unsure whether the AN used in ANFO is itself an ANBI - if AN is
> prilled for explosives purposes it might well be. Or perhaps it is
> controlled under one of the many AN control orders, which I have only
> a passing familiarity with.
>
>
> However there is another problem or three with ANFOs, AN water gels
> and emulsions - they need bigger holes than NG-dynamites or
> gelignites, as they will not explode properly when the diameter of the
> hole is small.
>
> In practice, combined with the fact that they are only about half as
> powerful, you end up using a lot more. Which means a lot more nasty
> gases to get out of your tunnel.
>
> Second, they really need boosters. There are cap-sensitive gels and
> emulsions, but then you are getting into the same legal hassles as the
> higher velocity explosives - plus you need different certificates and
> licenses for the boosters. Some people use detcord as a booster, but
> the same requirement for an explosives certificate etc applies (in the
> UK).
>
> Third, and perhaps most important, especially when used for tunnels in
> hard rock, they aren't really brisant enough to cope with hard
> granite. The NG-based (or NC-based) high velocity explosives produce
> shock waves which will fracture granite, but the lower velocity of
> detonation of the AN-based explosives give more of a hard push than a
> breaking shock.
>
>
>> The granite I met here is so hard that a powerful rock-drill
>> (percussion plus rotation) could not drill with a four-cutting-tips
>> cutter - had to revert back to a carbide-tipped chisel-edge drill.
>>
>> Implies that need a goodly blasting medium.
>
> Indeed. Gelignite, or a NG-dynamite, seems called for.
>
> Also, for a a small tunnel, AN-based explosives are generally less
> useful - though they do make small diameter cap-sensitive AN
> emulsions, AN-based explosives are generally better for larger
> charges.
>
> You didn't say how long the tunnel is, but unless it is very long
> jelly/NG might even be cheaper. It will certainly be more practical
> and need less drilling.
>
> BTW, Cranfield sometimes do a short course on mining explosives.
>
> Peter Fairbrother

Thanks Peter
Amazing info.

I'll cover a later question first.
The tunnel would not be long. Metres to tens of metres if I infer
rightly.
Would be a crosscut from an existing working in one lode to intercept
another lode.
There are mine and mineral charts of the area which lead the
suggestion to be made. Far beyond me to even know what this
information is, let alone how to interpret it yet.

I'll go to another implicit question.
The new crosscut would be down a small decline I have not been down
yet. So I don't know if that part is granite (hard) or killas
[metamophosed sedimentary rock] (brittle; readily drilled).
About half the mine is hard granite (dry); about half is killas (like
standing in a shower sometimes).

So your point about "nitro" blasting material points to more
questions. Thanks - will pursue that.
Meaning the traditional very brisant blasting material.

If the crosscut is in hard granite then another constraint might
present itself - the drill-hole I tried was clearly the size for
sticks of jelly. That was running at about the claimed 0.3m/min with
the powerful rockdrill used
http://weldsmith.co.uk/tech/minerals/condurrow/231207_rockdrill1st/231224_holman_silver_900.html
"rock-drill of 07Dec2023 - Holman Silver 900"
This is apparently a monster machine which can only be used on hard
granite.
So if it's on its "sweet-spot" with a drill for jelly then a bigger
drill for ANFO might be beyond possible.
Noting this "mega" rock-drill cannot run a 4-tips jelly-sized cutter
in the hard granite - has to be a chisel-edge cutter.
Thanks for makign that point.

This is not a workplace. It's a hobby activity. So...
The only way drilling can be done is with a "carryable"
"human-operated" drill (cannot be a "jumbo").
Hence you might be raising a very good point.

Well, wow, thanks so much.

One of the enthusiusts / volunteers at the mine is sending me
info. and giving me some guidance.
So hopefully all will be well.

If you want to "PM" me there is a contact form on my website, at the
"Index" and other pages.

Best wishes and a successful happy new year,
Rich Smith

PS thanks for "Cranfield" lead. Did my welding engineer Masters
there, including my fatigue of metals / welds project. Could look
whether that blasting materials course can be done.

"Jim Wilkins" <muratlanne@gmail.com> writes:

> "Richard Smith" wrote in message news:lybkaoe9k3.fsf@void.com...
>
> Further to original post:
> I have looked on-line.
> Going for the very specific search
> "electronic timer blasting"
> lead me to
> "electronic detonator blasting"
> with many relevant finds.
> Seems is a big industry.
> Hopefully by what I learn and by going for more very specific searches
> I can find my way into this topic.
>
> One example find is
> https://www.epc-groupe.co.uk/products/
> where they list many products for blasting.
>
> Different "takes" on the matter are appreciated.
>
> -----------------------------------------
> https://miningandblasting.files.wordpress.com/2009/09/rock-excavation-handbook-tunneling.pdf
> "Large cut holes are normally drilled by reaming. First, a smaller,
> for example, 45mm diameter hole is drilled then
> reamed to the final size using a pilot adapter and a reaming bit."
>
> "Big, uncharged cut holes (76 - 127mm dia.) [3-5"] provide an opening
> for the blasted, expanding
> rock from the surrounding cut holes."

I want to give thanks to you and the group for all your guidance and
contributions.
On 17 Dec 2023 all was ahead of me.
On 20 Dec 2023 when you gave the
https://miningandblasting.files.wordpress.com/2009/09/rock-excavation-handbook-tunneling.pdf
link I couldn't understand or follow what it was saying.
With own reading-around - books and online - and help here, it makes
sense now.

So on this first day of 2024 - my best wishes to all of you.
Rich Smith

"Richard Smith" wrote in message news:lymstoonac.fsf@richards-air-2.home...

"Jim Wilkins" <muratlanne@gmail.com> writes:

I want to give thanks to you and the group for all your guidance and
contributions.
On 17 Dec 2023 all was ahead of me.
On 20 Dec 2023 when you gave the
https://miningandblasting.files.wordpress.com/2009/09/rock-excavation-handbook-tunneling.pdf
link I couldn't understand or follow what it was saying.
With own reading-around - books and online - and help here, it makes
sense now.

So on this first day of 2024 - my best wishes to all of you.
Rich Smith

--------------------------------
It seemed to have been written for miners who already knew how to drill a
hole but not why or where.

This has diagrams of the sequential blast pattern opening up the central
uncharged borehole.
https://www.eoas.ubc.ca/courses/eosc547/lecture-material/Topic4-HardRockTunnellingMethods.pdf

Did you read Hudson Maxim's dynamite book? It's quite funny as long as
mental images of flying body parts don't bother you.

"Jim Wilkins" <muratlanne@gmail.com> writes:

> ...
>
> Did you read Hudson Maxim's dynamite book? It's quite funny as long as
> mental images of flying body parts don't bother you.

I had a quick look, copied the links to my files and bookmarked them
in the browser.
I have insomnia - could wrap up warm and read them.

I've worked in heavy industry and construction, so of nature do dark
humour with the reality of always looking out for yourself and others.

"Richard Smith" wrote in message news:ly34vgtk1n.fsf@richards-air-2.home...

I've worked in heavy industry and construction, so of nature do dark
humour with the reality of always looking out for yourself and others.

-------------------------

Maxim was willing to admit that he blew his hand off from inattention caused
by lack of sleep. I put off chainsawing and similar dangerous tasks until
wide awake; this morning I'm posting instead of finishing a job on the roof
for that reason. I regretfully quit night school because enough evening
coffee for 2 demanding classes and the late commute home kept me from
getting enough sleep.

"Jim Wilkins" <muratlanne@gmail.com> writes:

> ...
>
> Did you read Hudson Maxim's dynamite book? It's quite funny as long as
> mental images of flying body parts don't bother you.

I've got 2/3rds of the way through the first one.

There is a message you want me to get ? !
Something you want me to know, which you cannot say yourself but you
know this is exactly the right voice saying it?

There's a few general themes emerging from all those hundreds of
seemingly disparate stories.

"Richard Smith" wrote in message news:ly34vflb5k.fsf@void.com...

"Jim Wilkins" <muratlanne@gmail.com> writes:

> ...
>
> Did you read Hudson Maxim's dynamite book? It's quite funny as long as
> mental images of flying body parts don't bother you.

I've got 2/3rds of the way through the first one.

There is a message you want me to get ? !
Something you want me to know, which you cannot say yourself but you
know this is exactly the right voice saying it?

There's a few general themes emerging from all those hundreds of
seemingly disparate stories.

-------------------------------------
No, nothing personal. Really they were the only tales of working and playing
with nitroglycerine that I'd read online, when they appeared on Gutenberg's
recently added page. They are too old to describe current practice, but like
steam engines the evolving tech of those days interests me.

Hudson's brother Hiram took off in a winged and powered airplane before the
Wrights, but they were the first to be able to fly the same plane again.
https://engines.egr.uh.edu/episode/210

Missing fingers was fairly common among young chemistry students -- I still
have all of mine.

"Jim Wilkins" <muratlanne@gmail.com> writes:

>> ...
>>
>> There is a message you want me to get ? !
>> Something you want me to know, which you cannot say yourself but you
>> know this is exactly the right voice saying it?
>>
>> There's a few general themes emerging from all those hundreds of
>> seemingly disparate stories.

> No, nothing personal. Really they were the only tales of working and
> playing with nitroglycerine that I'd read online,
> ...

The message I get is similar to the one about oxy-acetylene equipment
- welding and cutting.
You do not mess around with it. You do not improvise. You take it
out of the box and you use it "by numbers" according to instructions.
If it doesn't work as-is you stop.
Oxy-acetylene equipment is a good way to investigate reincarnation.

All other welding equipment - you rig, frig, improvise, adapt, oil
where you have to - all sorts of things.

The situation is vastly more complex for these blasting substances.
But there are some recurrent themes where things went wrong.
Hopefully they will lodge in my mind and activate if I meet like
situation.

There's potassium chlorate preparations in the book I already have -
reprint of Guttman, "Blasting", 1906.
He is dismissive of them, saying don't be distracted off NG-based
media - jelly and dyna.
Hudson Maxim - his treatment of the topic!
Apparently relevant? No. Calibration of judgment - definitely.

Hudson Maxim's eloquent way of saying a lot with a few words:

"Now it happens that there is so much erraticism about high explosive
mixtures with chlorate of potash as a base that the pathway of
invention of such compounds has been strewn with the wreckage of the
hopes and anatomy of their inventors."

"Richard Smith" wrote in message news:lyo7e3miyy.fsf@void.com...

Hudson Maxim's eloquent way of saying a lot with a few words:

"Now it happens that there is so much erraticism about high explosive
mixtures with chlorate of potash as a base that the pathway of
invention of such compounds has been strewn with the wreckage of the
hopes and anatomy of their inventors."
------------------------------------
His style reminds me of Ambrose Bierce.

"The poets would have us believe that all of the great inventors and
discoverers, scientists and philosophers, have been far inferior to the
poets. The poets would have us believe that all the triumphs of chemistry
and mechanics have been small compared with the triumphs of poetry. The
poets would have us believe that the invention of the phonograph, of the
telephone, of wireless telegraphy, the discovery of radium and the X-ray,
the discovery of gravitation, are not equal to such triumphs of the poets as
“Aurora Leigh,” “Curfew Must Not Ring Tonight,” and “The May Queen.”
-HM

"Jim Wilkins" wrote in message news:un2c3s$2u4u6$1@dont-email.me...

His style reminds me of Ambrose Bierce.

https://www.gutenberg.org/files/972/972-h/972-h.htm

I read that bit... :-)

"Jim Wilkins" <muratlanne@gmail.com> writes:

> "Jim Wilkins" wrote in message news:un2c3s$2u4u6$1@dont-email.me...
>
> His style reminds me of Ambrose Bierce.
>
> https://www.gutenberg.org/files/972/972-h/972-h.htm

You are a cultured person.
I have a simple technical-algorithm mind which obsesses on bashing,
banging and other low-tech treatments, all serving fixations too
narrow for anyone else to have even seen the question could be
identified - until I come up with something "new and revolutionary" by
reason of no-one ever having been there to pursue such an archane
question...
:-)

On 20/12/2023 21:59, Snag wrote:
> On 12/20/2023 9:19 AM, Jim Wilkins wrote:
>> "Richard Smith"  wrote in message news:lybkaoe9k3.fsf@void.com...
>> https://www.epc-groupe.co.uk/products/
>> where they list many products for blasting.
>> ------------------------------
>>
>> This shows the speed of non-electric blasting cord:
>> https://www.youtube.com/watch?v=i6k26SJFyB8

erm, probably not quite.

They may well have used Nonel for the leadline from the exploder to the
trunklines along the bridge, and possibly for the downlines from the
trunklines to the charges, but the trunklines along the bridge were
detcord, not nonel.

tl-dr:

at 04s18f the trunkline on the nearest section detonates. It is clearly
not a nonel detonation, far too visible and extensive for anything but a
detcord detonation. (nonel detonations are hard to see in daylight,
especially at a distance).

Note also that the detonation is both begun and over within the frame,
there is no visible travel along the trunkline to be seen.

At 30 fps one frame takes 33ms; the main span is 50m, so at 6km/s the
detonation takes 8ms; the detonation is over well within one frame,
though its effects may take longer to manifest.

at 04s19f the trunkline on the center section detonates.

at 04s21f the trunkline on the far section detonates.

The delays between the sections are deliberate. One reason for using
delays is to minimise acoustic and overpressure loads.

at 05s00f the first two main charges blow

at 05s01f the next two charges blow

at 05s02f the last two charges blow

To step single frames in youtube pause the video and use the < and > keys

>
> IIRC primacord detonation head propagates at about 2000 meters/second .
> I only got to play with it once or twice but it sure was fun !

Detcord/Primacord (usually plasticised PETN, loadings for transfer cord
go from about 1.5 gram per meter to about 10 g/m, effects cords go to
about 50 g/m) is usually about 6 km/s or a little higher.

Nonel (which is a tube dusted on the inside with PETN powder held in
place by electrostatic attraction) is about 2,100 m/s

You can hold detonating nonel in your bare hand, though I'd recommend
gloves. Try that with detcord and you will lose fingers at best.

Nonel speed: https://www.youtube.com/watch?v=uFQdcKJUijQ&t=3156s

Peter Fairbrother

"Richard Smith" wrote in message news:lyv88aycwi.fsf@void.com...

"Jim Wilkins" <muratlanne@gmail.com> writes:

> "Jim Wilkins" wrote in message news:un2c3s$2u4u6$1@dont-email.me...
>
> His style reminds me of Ambrose Bierce.
>
> https://www.gutenberg.org/files/972/972-h/972-h.htm

You are a cultured person.
I have a simple technical-algorithm mind which obsesses on bashing,
banging and other low-tech treatments, all serving fixations too
narrow for anyone else to have even seen the question could be
identified - until I come up with something "new and revolutionary" by
reason of no-one ever having been there to pursue such an archane
question...
:-)
---------------------------
At a Mensa party several of us who had made careers of innovation and
problem solving considered the question of how to design a computer
algorithm to assist us. We concluded that we don't know where our new ideas
come from, subconscious memory associations can't account for all of them.
As Taylor Swift wrote in the Pattie Boyd interview:
"But there are mystical, magical moments, inexplicable moments when an idea
that is fully formed just pops into your head."

Since industrial innovation is usually too competitive to reveal in print
I've looked at artistic innovation, such as the analysis of song meanings,
as much for why they chose their words as what they meant to say. I'm
convinced that Bob Dylan's lyrics were chosen to rhyme and prompt the
audience to apply their own interpretations to them. Last night on TV a
program on painter Edward Hopper held that the critics had seen more in his
paintings than it was eventually revealed that he intended.

https://blog.artsper.com/en/a-closer-look/artwork-analysis-nighthawks-by-edward-hopper/
The enigmatic couple are the painter and his wife, who was also a talented
artist and capable chronicler of his work. She wouldn't let him use any
other woman as a model.

"Richard Smith" wrote in message news:lyv88aycwi.fsf@void.com...

You are a cultured person.
I have a simple technical-algorithm mind which obsesses on bashing,
banging and other low-tech treatments, all serving fixations too
narrow for anyone else to have even seen the question could be
identified - until I come up with something "new and revolutionary" by
reason of no-one ever having been there to pursue such an archane
question...
:-)
---------------------------

You may be a product of your environment. By Alistair Cooke:
https://www.bbc.co.uk/programmes/articles/2MKhm99hgpBrV79K47Mycbh/persian-poets-need-not-apply-29-march-2002

"None of my friends in England had ever heard of biology until and unless
they were going into a science which in those days put them outside the pale
of cultivated company."

"I'm sure this has all changed since nearly a half a century ago when the
late CP Snow raised a cultural storm, especially in the ancient
universities, by saying that in England then there were two cultures that
lived side by side in mutual incomprehension and even hostility."

"There was the culture of literary arts people who think of themselves as
the cultivated and there were the physical scientists who may know little
literature but are amazed at the narrowness, the constraint, the literary
intellectuals' ignorance of so much of the life and the world about them."

"The man - his name was [Harold] Macmillan - wrote in his diary, after he'd
spent some days and evenings with the general [Eisenhower], he wrote: "He is
a man of charm and candour and determination but I fear woefully
ill-educated."

"But whereas Mr Macmillan found Eisenhower deficient I imagine in quotations
from Virgil and Wordsworth, he was woefully ill-educated in mathematics,
engineering, strategy and tactics, especially the economics of industrial
warfare about which Eisenhower's prescience had made General Marshall insist
he become supreme commander."

Macmillan's reaction to Americans:
"We, my dear Crossman, are the Greeks in the American empire. You will find
the Americans much as the Greeks found the Romans—great big, vulgar bustling
people, more vigorous than we are and also more idle, with more unspoiled
virtues, but also more corrupt. We must run AFHQ (Allied Forces
Headquarters) as the Greek slaves ran the operations of the Emperor
Claudius".

Americans weren't totally ignorant of the classics, Patton used Caesar's
operations as a guide to where the low ground was firm enough for vehicles,
and raced him to bridge the Rhine.