Tuesday 30 April 2013

Mad Jack

Today I was on the trail of mad Jack Fuller and his many follies.  In the late 16th century, after what appears to have been many years of philanthropic donations, Jack decided to spend some money on himself.

I first found his 'Sugar Loaf'.
13 04 30 Jack Fuller - Folly - Sugar Loaf
Which handily enough had a trig pillar nearby - no idea why it is called Jury's Gut.
13 04 30 TP4140 - Jurys Gut
I then drove towards the Obelisk.  I am obviously well trained to find (or not) trig pillars and therefore approach each new find wondering if I am going to spot it or not. As if I'd miss this!
13 04 30 Jack Fuller - Obelisk
What you can't see from the photo is that it has a wee moat around it.  Cute!

I then drove into Brightling and stopped by the church
13 04 30 Jack Fuller Tomb - Brightling (3)
having noticed something somewhat egotistical in its graveyard.
13 04 30 Jack Fuller Tomb - Brightling (1)
Jack's tomb in case you hadn't guessed.
13 04 30 Jack Fuller Tomb - Brightling (2)
And then I saw the tower and drove towards that.
13 04 30 Jack Fuller - Tower
What fun - the gate on the tower was unlocked and I could climb up inside.  Health and Safety eat your heart out.
 13 04 30 Jack Fuller - Tower
I spotted the temple from the tower but decided not to walk over to physically touch it.  Sometimes a distant shot is enough.
13 04 30 Jack Fuller - Temple
Which is just as well as the next trig I tried to bag didn't quite come good.  I was stopped on the edge of the field by the owner (?) asking what I was doing. I told him I was simply after the trig but he explained there was no public right of way (confession - I had passed a sign saying so) and that he was trying not to encourage people to visit it.  Looking at the trig pointing website for this trig it appears I'm the first to have encountered any difficulty.

Anyway, we had a little chat and he let me take a photo from a distance.
13 04 30 TP2735 - Darwell Wood
We then carried on our conversation as I left.  He thought there were more exciting things I could be doing with my spare time (oh how little he knows) but it turns out his daughter is an MRICS rural surveyor.  We had a pleasant chat about Jack Fuller and I wouldn't say we were bosom buddies by the time we parted, but he certainly isn't going to sue me.

So that's Jack and what a mad and fascinating guy he must have been.

Monday 29 April 2013

Herstmonceux and Long Man

My daughter has work experience at the Space Geodesy Facility, Herstmonceux, so I'm in East Sussex for the week with her.  After dropping her first thing today I just had to sweep up the 3 trigs in the Herstmonceux grounds.

I've yet to work out the raison d'etre for there being 3 here although the names are a bit of a clue.

First we have 'Solar'.
13 04 29 Herstmonceux - TP0011 - Solar
Which has a mighty fine receiver on top.
13 04 29 Herstmonceux - TP0011 - Solar
And an SLR for a backdrop.
13 04 29 Herstmonceux - TP0011 - Solar
Next we have 'Transit Meridian'.
13 04 29 Herstmonceux - TP6562 - Transit Meridian
No longer monitoring anything and looking somewhat sad for itself.
13 04 29 Herstmonceux - TP6562 - Transit Meridian
And finally we have just plain and simple 'Herstmonceux' which is sitting in front of a magnificent old observatory.
13 04 29 Herstmonceux - TP3747 - Herstmonceux
So that was 3 trigs bagged by 0915.  I suspect I will never trump that.

Later on in the day I headed to Wilmington.  On the side of the ridge is the Long Man of Wilmington.
13 04 29 Wilmington - Long Man
And then on the top Wilmington trig.  Newer than the chalk man and to most people far less interesting.
13 04 29 Wilmington - TP6953 - Wilmington Hill
It was pretty windy up there but the views were wonderful.
13 04 29 Wilmington - TP6953 - Wilmington Hill
Back to Herstmonceux tonight.  Hopefully if the skies are clear we get to play with lasers.  How much fun can one possibly have?

Sunday 21 April 2013

Three Trig Sunday

A 3 trig day today. First off tackled one that had eluded me last year. I'm not the only one and others have struggled to find Lowman's Farm. That made it even more appealing for a hunt so in jeans, long sleeved top and gardening gloves I set out to find it. Actually, it was easy to spot from the road. Just a pig to get to and I had to fight through brambles to get to touch it (it's not a true trig bag unless you have contact with the trig). I drew blood on a thorn at one point which made it even more fulfilling. The best trig hunts are the ones you fight for.
13 04 21 TP4574 - Lowmans Farm
Some damage to the top.
13 04 21 TP4574 - Lowmans Farm
Next off was an easy one, Widworthy Hill. Now isn't this a beauty?
13 04 21 TP6939 - Widworthy Hill
Plug intact. Sight holes blocked. Fine views across East Devon.

Lastly it was Longbridge Farm. I was a tad nervous about this as the descriptions mentioned circumnavigating fields of bullocks which is not my thing. However, a clear run on farm animals and, give or take the odd thorn in my hand, a nice find.
13 04 21 TP4529 - Longbridge Farm
This is what weekends are for.
 

Thursday 18 April 2013

Hunting Great Theodolites

Ever since I bumped into a Great Theodolite in Cape Town in 1995 I have been transfixed by these massive, beautiful instruments.
 Everest theodolite 1995
From my research I believe there have been six large theodolites. The first two were built by Ramdsen.  The first was bought by the Ordnance Survey of Great Britain and the second, although commissioned by the East India Company, was deemed too pricey and also bought up by the Ordnance Survey. The third was ordered by Switzerland in the late 18th Century but never quite made it there before it was cannibalised (some French/Swiss warfaring got in the way).

The East India Company turned to William Cary and Barrow to make them a theodolite of similar size (late 18th C, early 19th).  In the early 19th Century they ordered another theodolite from Troughton and Simms.  And another theodolite was ordered mid/late through the 19th Century. This last one was made of steel and even heavier than the previous theodolites.  It proved too heavy to be of use to lug up mountains and was eventually sent on permanent loan to the Cape Observatory.

The first theodolite was destroyed during the second world war when the Ordnance Survey HQ was bombed.  The second resides in the Science Museum in London.  The third is no more.  The fourth is in the Survey of India offices in Dehra Dun where it is given pride of place next to the Assistant Surveyor General of India's office.  No idea of the fifth but it may be in Calcutta but I've heard no mention of it so preusme it is no more.  And the sixth is in Cape Town (again below).
08 01 03 The Great Theoolite
So of all the extant great theodolites I've seen them all - the Science Museum in London, Cape Town and, last but not least, the Dehra Dun theodolite.
13 04 03 Dehra Dun Survey of India
13 04 03 Dehra Dun Survey of India
The Harris and Co inscription on the vertial circle is confusing me.   Although the horizontal one is etched with Barrow 1833 which fits in with my research.
13 04 03 Dehra Dun Survey of India
To wind the clock back a tad, Ken and myself have been after this theodolite for a while (or was it just me?).  When we realised that we were within spitting distance of Dehra Dun this spring we invited ourselves to visit the Survey of India offices.  Once we arrived in Dehra Dun you can imagine the excitement (OK, mine) when I realised that our Dehra Dun hotel was under 30m from the entrance to the Survey of India offices.  Ken and I went for an explore.
13 04 03 Dehra Dun Survey of India
And we got more excited as we walked down the road.
13 04 03 Dehra Dun Survey of India
OK, you can call us sad, but I prefer to say 'inspired'.
13 04 03 Dehra Dun Survey of India
And here we are.
13 04 03 Dehra Dun Survey of India
We had tea with the Assistant Surveyor General of India - how humbling is that? - and then the great theodolite photos.  Awesome.

As if that wasn't enough geo excitement in one day, on our way down town that evening to celebrate our 'theodolite bag'  we passed a familiar Ruth sight.
13 04 03 Dehra Dun Indian Hydrograhpic Office
By the time we'd finished the photo shoot we were surrounded by over 15 Indian guys with very quizzical looks on their faces.  You could see the thought bubbles coming out of their head: to summarise I think most of them said "crazy woman".
13 04 03 Dehra Dun Indian Hydrograhpic Office
The next day we were privileged to go to another Survey of India office which included their museum.
13 04 04 Dehra Dun Survey of India
We said hi to Everest on the way in.
13 04 04 Dehra Dun Survey- Everest
We spent over an hour soaked in surveying memorabilia - Everest's telescope, the transit telescope of the Great Arc of India, subtense bar, drawing instruments from Montgomery, surveying subterfuge (prayer beads used to survey in Tibet - pray and survey simulataneously) and the most amazing tidal harmonic calculating machine I've ever seen.  Sadly we couldn't take photos but I was gobsmaked by the surveying gems we found.  Absolutely wonderful stuff in the survey capital of India.

Wednesday 17 April 2013

Old Delhi - Red Fort Finds

The Red Fort, Old Delhi, is a 17th Century Fort once residence of Mughal Emperors.  During it's time it has seen many rulers come and go and was lastly occupied by the British in the 19th Century.  It is now a UNESCO World Heritage Site.
13 04 02 Red Fort
I suspect it lost its grandeur through British occupation and is a shadow of its former self.  The Archaeological Survey of India now own it who no doubt added the artefacts I found in a small museum there.  These pieces appear to relate to the time around when the Red Fort was built.

Brass astrolabe, top left hand corner.  Any idea what the other instrument is in the picture?
13 04 02 Red Fort (36)
A brass celestial sphere.
13 04 02 Red Fort
And a bronze one.
13 04 02 Red Fort
All lovely surveying history.

Delhi Observatory - Jantar Mantar

I have recently returned from a trip to India.  Lots of really good surveying fun (and, no, that is not an oxymoron).  I travelled with my daughter.  We spent most of our time in Delhi, but popped up to Dehra Dun for some theodolite worshiping at one stage.  More about that another day.

This first blog is about Jantar Mantar in New Delhi which was a tremendous find.  To quote from various boards around the site...

"This jantar mantar is the oldest of a unique set of 18 century observatories constructed by Jai Singh II.  It is one of five built from 1724 onwards as directed by Mughal emperor Muhammad Shah to revise the calendar and astronomical tables.

"The Samrat Yantra of the ‘King of Instruments’ is the largest and most imposing of the yantras at the Delhi Observatory.
13 04 02 Jantar Mantar
"This yantra exists in all the extant jantar mantars and is counted amongst Jai Singh’s high precision instruments. A chamber in its eastern quadrant contains another yantra called the Shasthamsa Yantra.

"Measurements: 20.73m high, 38.10m from east to west and 34.60m from north to south.
13 04 02 Jantar Mantar
"Function: Measurement of the apparent solar time or local time of a place and the sun’s declination.

"Working: The yantra consists of an inclined wall parallel to the earth’s axis flanked by two semicircular quadrants. All these surfaces have scales marked on them.  The quadrants represent the place of the equator and are marked in hours, degrees and minutes. The time at a given moment may be read by the shadow of the included wall (or gnomon) on the quadrants.

"The misra or composite yantra is composed of five different instruments. This yantra is unique to the Delhi Observatory. It s believed to have been constructed by Maharaja Madho Singh (1751-68), the son of Maharaja Sawai Jai Singh II.  The five component yantras are the dakshinottara bhitti, samrat (in two halves), niyat chakra, karka rasivalaya and the western quadrant.
13 04 02 Jantar Mantar
"The dakshinottara was also built in the Jaipur, Ujjain, Varanasi and Mathura observatories. It is a modified version of the portable meridian dial present in Greek, Arabic, Hindu and European systems of astronomy. The dakshinottara bhitti of the misra yantra is in the form of a graduated semicircle located on the eastern wall.

"Function: Measurement of the meridian altitude of a celestial object. It is most suitable for measuring the altitude of the sun.

"The niyat chakra or ‘fixed arc’ occupies the centre of the misra yantra. It consists of four semicircular scales on either side of a central gnomon. The scales are included to the meridian plane at different degrees.

"Function: Measurement of the declination of an object at intervals of a few hours as the object moves east to west in the sky during the period of the day. The niyats are apparently meant to duplicate the readings for the meridian arcs at four different locations the globe: Notkey in Japan, Serichew in Pic Islands, Zurich in Switzerland and Greenwich in England.

"The karka rasivalaya or circle of the sign of cancer consists of the large graduated semicircle marked on the northern wall of the misra yantra. This wall is inclined to the vertical at an angle of about 5 degrees, and is parallel to the plane of the tropic of cancer. On June 21, when the sun is at the tropic of cancer, its rays graze the instrument at noon.

"Function: Measurement of the longitude of a celestial object, such as the moon at the moment when the first point of the sign of cancer is on the meridian. It was designed to measure to the nearest minute of an arc.

"The samrat yantra of the misra yantra is construction in two halves to be used before and after the noon hour.

"Function: Determining the local time.

"The taller western quadrant of the misra yantra has sometimes been identified as an agra or amplitude instrument.

"Function: Apparently for measuring the latitude and longitude of a celestial object once every 24 hours.

Near the back of the jantar mantar are a couple of circular buildings - rama yantra.  These are best described as a large hollow drums with their top ends uncovered and a pole erected in the centre.
13 04 02 Jantar Mantar
The observer could walk along the scales to make the necessary observations. 
13 04 02 Jantar Mantar
Or to have your photo taken.
13 04 02 Jantar Mantar
Scale marked in the uprights.
13 04 02 Jantar Mantar
A very comprehensive report on all things yantar mantar can be found here.

Now I want to visit the rest!