Cryptic surveying instrument

[Michael Lever]

At the risk of displaying what may be my gormless ignorance,

Can anyone explain the markings on the sight staff, that J. Mulvaney is holding in the attached image?

The image is dated to 1966, and is from:

Mulvaney, J. 1990: Prehistory and heritage : the writings of John Mulvaney. Dept. of Prehistory, Research School of Pacific Studies, Australian National University, Occasional Papers in Prehistory. 17.

Cheers,

Michael

[John Pickard]

I’ve never seen one Michael, but there are major divisions (1, 2, 3, ..) which appear to be feet; subdivided by a series of alphas and numerics: 1 T V 7 N referring to divisions at 0.1, 0.3, 0.5, 0.7, and 0.9 feet respectively.

 

It appears to have been made in sections with the lower section ending  at about 3.4, between the buckets. The overlapping join suggests that the sections swivelled on bolts so the sections were one behind the other when folded for carrying.

 

As I said, never seen one. I wonder if it was home-made on-site because he’d forgotten the real staff? Use of the mixed characters for the subdivision is a nice way of avoiding errors when reading. Using decimal feet is also pretty smart for reducing errors. Whoever made it (Mulvaney or a manufacturer), they came up with a very elegant solution.

 

Is it still extant?

 

Cheers, John

John Pickard
john.p...@bigpond.com

--

[tessa corkill]

Fascinating! A search in Google resulted in numerous incomprehensible sites, mainly Greek or Biblical; eg:

Grammatica graeca sacra Novi Testamenti

https://books.google.com/books?id=nvdbAAAAQAAJ - Translate this page

Georges Pasor - 1655

'JEtuíibVí9b» j ¡7vm&-»t j iTV7n<&M. Pluralis. 'ir viró fíente , {'таятсЭ-f 3 «тиэт»^. Formatur ab Aorifto fecundo Activ. mutatô •» Singularis. Tú-^tfiofverberabo ..

Make of them what you will!

Tessa C

--
You received this message because you are subscribed to the Google Groups "OzArch" group.
To unsubscribe from this group and stop receiving emails from it, send an email to ozarch+un...@googlegroups.com.
To post to this group, send email to oza...@googlegroups.com.
Visit this group at http://groups.google.com/group/ozarch.
For more options, visit https://groups.google.com/d/optout.

[Richard Wright]

Michael

The staff is scaled in decimal feet.

The smaller characters represent:

1: one
T: three
V: five
7: seven
N: nine

You are not gormless, but alas I am old enough to have used such a staff.

Richard

At 09:48 AM 31/08/2015, you wrote:

At the risk of displaying what may be my gormless ignorance,

Can anyone explain the markings on the sight staff, that J. Mulvaney is holding in the attached image?

The image is dated to 1966, and is from:

Mulvaney, J. 1990: Prehistory and heritage : the writings of John Mulvaney. Dept. of Prehistory, Research School of Pacific Studies, Australian National University, Occasional Papers in Prehistory. 17.

Cheers,

Michael

--
You received this message because you are subscribed to the Google Groups "OzArch" group.
To unsubscribe from this group and stop receiving emails from it, send an email to ozarch+un...@googlegroups.com.
To post to this group, send email to oza...@googlegroups.com.
Visit this group at http://groups.google.com/group/ozarch.
For more options, visit https://groups.google.com/d/optout.

Content-Type: image/jpeg; name=P_20150830_142706.jpg
Content-Disposition: attachment; filename=P_20150830_142706.jpg
X-Attachment-Id: 9e47a4bd-b88d-4fe7-b028-6f0960a62058
Content-ID: <9e47a4bd-b88d-4fe7-b028-6f0960a62058>

******************************************************
Richard Wright
72 Campbell Street
Balmain
NSW 2041
Australia

Phone: +61 2 98181037

Alternative email address: ric...@cranid.com
*******************************************************

---

This email has been checked for viruses by Avast antivirus software. www.avast.com

[Peter Marquis-Kyle]

Just to add to John Pickard's observations, I notice that each of the
letters is drawn with a height of 0.1 feet so that, for example, the top
of the V indicates x.5 feet, and the bottom of the V indicates x.4 feet.

Of course, most dumpy levels read upside-down in those days, so what
looked like the 'top' was actually the 'bottom'...

--

Peter Marquis-Kyle

[den...@tpg.com.au]

Older cheap dumpy levels, telescopic alidades etc often did not have a correcting lens, which meant that your image was seen upside down, rather than normal.

The lettering reduces the chance of a mis-read if the image is upside down - 6 and 9, 2 and 5.  It probably does that better than the modern 'piano-key' staff arrangement would in that way.

My impression is that decimal feet were bigger in US survey practice than in the UK.  Certainly all of the classic 1930s Works Administration dig reports report in decimal feet.

Denis

----- Original Message -----

From:

oza...@googlegroups.com

To:

<oza...@googlegroups.com>

Cc:

Sent:

Mon, 31 Aug 2015 10:54:46 +1000

Subject:

Re: {OzArch} Cryptic surveying instrument

[Richard Morrison]

John Mulvaney has advised that the staff belonged to Dermot Casey who probably used it at Verulanium in the 1930s (Wheeler's excavations). 

Richard Morrison
 

---

From: "den...@tpg.com.au" <den...@tpg.com.au>
To: oza...@googlegroups.com
Sent: Monday, 31 August 2015, 11:19

[Garry Law]

Couldn’t access the photograph – but having held a survey staff often enough in Aus and NZ and having used a standard inverted image Dumpy level (standard - not a cheap option) I can confirm engineering surveying in Aus (and NZ) was in decimal feet. The staff sounds like a light weight one rather than a standard telescopic staff, and a hard one to operate if there was any wind.  With a bit of practice the scale is easy enough to read.  The tricky bit with a decimal feet scale was when one had to set levels in a building where they were dimensioned in feet and inches and occasionally eights of an inch. An eighth inch  is 1/96 of a foot  that 0.0104 feet.  The trick was to find the nearest part of a foot – so it one was setting a level to  some number of feet plus 4 and a half inches one would take 4 as  .333 feet and add  4 x 0.014 or 0.389,  except as one was not levelling to that precision anyway, the mental calculation was .33 + 4 x 0.01 or 0.37 which was a little out – but near enough and avoids having to do a calculation on paper – there were no electronic calculators to carry about!

Garry Law

31 Lansell Drive, Dannemora, Auckland 2016

lawas.co.nz     gl...@lawas.co.nz

Ph (64) 09 271 6505   Mob (64) 027 5665 764

**********************************