Artillery resection

[A Rankin]

I've been investigating the process of plane table resection and how long it took to complete the process and issue results to the battery.  Marble in British Artillery on the Western Front in the First World War: The Infantry Cannot Do with a Gun Less on page 237 stated that the process was "possible in around 40 hours" but the citation he gives (OH 1918, IV, 335) doesn't talk about survey, and was possibly a typo.

 

Does anyone have information on this or a pointer to a reference?  I've looked through Artillery Survey on the Western Front, Chasseud's Artillery's Astrologers did not help and the Report of Survey on the Western Front described the process but didn't give an indication as to time involved.  I'm looking specifically at Fourth Army during the fighting in early October as they broke through the Hindenburg, Nauroy and Beaurevoir lines.  The Australian Corps Topo section war diary gives numbers of battteries resected, but no indication of times.

[DavidOwen]

Have you tried asking the Ordnance Survey to see if they can help? https://www.ordnancesurvey.co.uk/blog/2015/06/mapping-world-war-one/

 

You may have already seen this, not sure it specifies how long it takes though https://www.scribd.com/document/37955008/Artillery-Firing-Instruction-on-Artillery-Fire-Part-IV-and-Part-of-Part-v

Edited 25 October , 2018 by DavidOwen

[JulianR]

Having been a surveyor, I think this is a bit like asking how long is a piece of string.   

 

The process involves measuring a number of angles between points of known co-ordinates, and the more points the better.

 

If we were using a plane table, which I got shown more than 40 years ago, then assuming that we arrive on the battery position, we need to identify at least three points of known co-ordinates, e.g. church spires etc., You would then need to draw the grid up on plotting paper, plot the points of known coords, orientate the plane table and measure the angles between them.  Check that the rays intersected and did not have a triangle of error, if they did then further work is necessary.

 

The following factors will come into play,

1) The skill of the surveyor

2) Visibility, including weather, nature of countryside etc.,

3) The number of points of known coords about, will you need to establish more?

4) Accuracy of plotting

5) Accuracy of observing the points of known coords

6) Is the battery position somewhere that can see plenty of points of known coords?

 

Unless you could find a Field Survey War Diary which specifically stated that they had surveyed in x batteries on day y, I am not sure that you will find an answer.  Even a skilled surveyor might not survey in two batteries in the same amount of time.  

 

Using Manual of Artillery Survey Part 1, 1932 War Office, I do not have an earlier edition, states that at 1:20,000 a fine pencil line represents an actual width of 5 metres, at 1 inch to 1 mile approximately 15 metres and an accuracy greater than this is not to be expected from the most skilled operator.

 

Quite recently on here I saw someone's PhD thesis on the changes in Royal Artillery practice on the Western Front which did mention, I think, how long it took for the surveyors to fix a Corps gun batteries, but did not I think mention how it was done.

 

Julian

[DavidOwen]

This is the only Field Survey War Diary that came up on TNA (should also be available on Ancestry?) http://discovery.nationalarchives.gov.uk/details/r/7df0a593a8204933891dbcc93c0bcc90

Had a quick squint through the watermarks but difficult to read.

[A Rankin]

David,

 

     Thanks for the pointers.  The firing instructions I hadn't seen and gave a bit more detail on the process, but didn't speak as to time involved. I've previously obtained the 5th Field Survey Company/BN for work on sound ranging and flash spotting, but they don't talk about resection from what I can read, as you say, the writing is on the difficult side to read.  I've left a comment on the blog post you provided and will try to get in touch with the author.

 

JulianR

 

    I figured there would be wide variability in times based on the factors you described.  From what I've been able to gather, the people who would have been doing the survey from the Australian Corps Topo sections would have been very experienced at the work. I don't have any solid information about the state of known landmarks, though this was the first time since 1914 that there had been fighting in this area.  I know that the Churches at Montbrehain and Joncourt had been damaged but were still standing, for example.  The 1:20000 map (Wiancourt) https://digitalarchive.mcmaster.ca/islandora/object/macrepo%3A4074/-/collection shows a number of benchmarks in the area. The weather on 4 October 1918 was misty and overcast.  Battery positions were clustered east and southeast of Joncourt.

 

From my understanding of the war diaries involved, all of the batteries (overall 8 Brigades of FA or 32 Batteries) had displaced on 4 October to new positions and were to be ready for action by 1800 that evening. Some artillery instructions on the 5th specified that the batteries get resected to support the attack which was scheduled to occur on 7 October (later changed to 8 October) by the 30th American Division (who relieved the 2nd Australian Division but retained the supporting artillery).  That and the Corps Topo Diary which stated only 20 resections were done in October tells me that they weren't resected, probably due to time constraints.  The info you have given me is valuable though in that the issues involved aren't conducive to a strict timetable and you explain well why that is the case.  Being able to say that it's not an easily measured process is helpful in itself. Thank you for that.

 

The Thesis you are talking about is likely Marble's as his book is derived from it.

 

Thank you both for your help.

[JulianR]

Believe the thesis was Jackson Hughes, Adelaide, 1992

 

Julian

[A Rankin]

I've skimmed previously, but hadn't really looked at him for this question. I've just  had another look through and In talking about the survey preparations before Cambrai, he gives a reference to a 'Lessons from Recent Operations, Field Survey Company" in WO 158/316. I'll get that digitized and see if that sheds some light.

 

Thank you

 

Adam

[JulianR]

Adam,

 

Benchmarks give height info only,  they are not normally in a position that you can set up over, usually being cut marks on walls etc., certainly in the UK.  You would also require to have a list of their coords to be of use.  Hughes, I thought was ok, but there were some sections where he was unclear in what he meant.  Certainly when talking about the use of BPs.  Once or twice I was not sure if he meant British or German artillery.

 

There used to be a list of the categories of Survey States, staring with A as the lowest, basically the GPO's greasy thumb print saying we are here, through to D, Theatre Grid, established by RA/RE survey troops, but I know that they changed in about 1980 to A and B, so do not know when A-D started.

 

Julian

[SapperBoo]

On 25/10/2018 at 05:21, A Rankin said:

I've been investigating the process of plane table resection and how long it took to complete the process and issue results to the battery.  Marble in British Artillery on the Western Front in the First World War: The Infantry Cannot Do with a Gun Less on page 237 stated that the process was "possible in around 40 hours" but the citation he gives (OH 1918, IV, 335) doesn't talk about survey, and was possibly a typo.

 

Does anyone have information on this or a pointer to a reference?  I've looked through Artillery Survey on the Western Front, Chasseud's Artillery's Astrologers did not help and the Report of Survey on the Western Front described the process but didn't give an indication as to time involved.  I'm looking specifically at Fourth Army during the fighting in early October as they broke through the Hindenburg, Nauroy and Beaurevoir lines.  The Australian Corps Topo section war diary gives numbers of battteries resected, but no indication of times.

The observation time for resection by plane table is very quick, 15 minutes.  However, this gives you the position of the plane table which is not necessarily the position of the batteries.  Positioning of the battery involves a second process usually a traverse from the resected point.  The most significant time factor is the logistics of identifying the point to be resected and getting to that point.

When I was fixing bearing pickets in Germany in the late 70's the challenge was usually time limited.  i.e. what is the best you can do in 4 hours.  I guess the same was true in WW1.

On 25/10/2018 at 14:09, JulianR said:

Having been a surveyor, I think this is a bit like asking how long is a piece of string.

I agree with JulianR.  It is a bit like asking how long is a piece of string.

 

Sapper Boo

 

PS I think I now know the source of the question I was asked at work last week.

Edited 5 November , 2018 by SapperBoo

[JulianR]

Well it wasn't me that asked it.  I  had left Germany by the late 1970's.  

[A Rankin]

SapperBoo,

 

    If it was via the Ordnance Survey blog, then that was me.  Thank you for your help in the matter.  I'd rather check these sorts of things with people who have practical knowledge if I'm not able to get a direct answer from historical sources as to how they did it at the time.

 

Adam

[SapperBoo]

35 minutes ago, A Rankin said:

SapperBoo,

 

    If it was via the Ordnance Survey blog, then that was me.  Thank you for your help in the matter.  I'd rather check these sorts of things with people who have practical knowledge if I'm not able to get a direct answer from historical sources as to how they did it at the time.

 

Adam

It was the sort of question that needs clarification.  The guy at work who asked me was an ex Gunner surveyor and I am an ex Sapper surveyor.  We had plane tables available in the 70's but I don't recall ever using them.

 

SapperBoo

 

[JulianR]

I think I got shown a plane table at Larkhill in the early 1970's but as far as I remember they were not issued to RA Survey Troops, neither were range finders or heliographs which we were also shown.  

 

Julian