The Voussoirs

The Voussoirs?  Sean and I found it harder to remember how we actually did them. We have more photos of the making and placing of them than any other aspect of the project and yet can't quite work out what was going on.  

Sean writes “ I think my own trepidation and associated stress levels were at a build high with them.  The voussoirs were going to be made from pre-cut blocks of granite from art city… for ‘simplicity’ we needed one size block to suit all voussoirs and another for the springers, there was little room for manoeuvre or mistakes.

Initially there was a lot of head scratching… we had started the build - and so had settled on actual dimensions  in terms of height and width of opening, before we settled on the arches.  Having established batters was important because with increased height there was going to be a point where they were actually getting wider as the curve exceeded the 1:10 of the outside.   So I sat down at home in Wales and calculated what maximum widths would be, and quickly realized that the keystone (who’s top would be the highest point of the arch and hence the widest point) would need to be longer than the rest for example.  

During design it was decided that there could be separate sets of voussoirs - front and back- that interlocking them (making them throughs) would be far to  complicated so we chose to have them present a straight seam when viewed from underneath, an so each would have a slightly different length.

I drew scale drawings, made all sorts of calculations and notes based on projected sizes provide by John on sketch-up and eventually came up with a size for the voussoir blocks, allowing for removal of waste for shaping plus a bit of wiggle room in case we needed to amend anything- psychic, or just tuned into the way we work, can you actually plan how to ‘work on the hoof’? I even drew a scale curve for the springers to make sure that when placed at right angles to the door the tail of the springer would still be outside the curve so that it could actually be cut from a given block -basically this inside wall edge was much longer than the exposed edge on the curved inside… the straight outside presented no such problem. " 

"One thing I was sure of from the outset was that however hard I/we tried the two openings would not be perfect there would inevitably be some variation of widths cross and/or through as it turned out one was close to perfect width wise, but with a slight difference through, the other was closer though but with an inch or so difference across. These all complicated the build in terms of centring the forms, having to prop the odd voussoir slightly struggling to get the pre-cut blocks to accommodate the springers, introducing all sorts of imperfections."

"When it came to processing the voussoirs it was decided to utilize one sawn edge and cut the other face at an angle and adjust the base to the correct angle to make life easier.  Much sawing, kerfing, chiselling and grinding to get rid of the waste and produce another clean edge.  Nasty, noisy, dusty if my stress levels were at a high, I think John was probably heading off the chart, his sticking at it and often driving it at this point is one of the greatest and yet invisible aspects of the whole build.  In the end I think the clean cuts and the eventual motif set everything else off and was well worth the angst.  

Back to the actual process, once the springers were cut the block was placed on the former on which I had marked the curve of the inside face by eye – pure guesswork given that the radius of the curve would in effect be changing as height was gained, but again as long as it was not obviously too straight or overly curved it would be imperfect but I hoped would look right as long as it ‘flowed’."  

"Initially I couldn’t remember how the angle of the second face was determined.  For the springers I think I ‘simply’ aimed a straight edge (level) at the centre of the circle for the arc of the former, but that was a foot or so below the actual bottom edge of the form and marked the line with that.  Clearly not a tenable approach for the whole process.  I had started putting these notes together a couple of days ago and then I had a restless night full of voussoirs, dust and nonsense which include John’s beard – possibly instigated by my own current attempts to grow one- , but clearly in the middle was a wooden template.  This was used to get the second angle, with the base slightly cut to get a better angle onto the former.  It didn’t all go according to plan. " 

                         

"All the voussoirs were cut for the front and placed before further processing (except the keystone) – that is batter of the face – a process repeated (more or less in tandem) for the inside.

I can’t remember how I marked the curve of the face on the inside voussoirs, clearly it wasn’t with my profile as the wooden form stuck out and was in the way… maybe a template?  I have a picture of the keystone in place with markings… maybe I aimed at this… One edge would certainly have been marked by scribing against the previous stone, it is clear that there was quite a bit of variation in the end.  When viewed close up the curve gets distorted, and the voussoirs are not of a uniform height and extrados does not necessarily parallel the intrados.  All sorts of imperfections but it wasn’t worth trying to iron out the minor discrepancies given the dangers inherent in 'killing' a stone."

The accumulative connection.

Recently on Instagram I posted a photo of the Temple of Imperfections. I explained in the text that the installation was  called the Temple of Imperfections, because of all the many imperfections that can still result in a kind of perfection that can't be achieved any other way.

We imagine that the almost imperceptible, deviations from perfectly level, perfectly straight, perfectly curved , perfectly this or that, may all serendipitously mesh together and cancel each other. 

I would venture to say there isn't an imperfection that can't be corrected with another. While there may be many planned attempts at correcting something so that it nears perfection, there is still the likelihood the 'imperfect fix' might actually create something closer to perfection, than the over-planned, tightly prescribed, uncompromising fix. 

When laying stones, it is possible to come to what we would accept as 'perfectly level', by having stacked that course of stones along the top of several rows of stones below, that were decidedly, 'off level'.

In writing now, in several blog instalments, about how the temple came to be made, and about this concept of accumulative imperfections, I realize that it is a kind of nod to (as well as a bit of a departure from) the Japanese aesthetic of wabi-sabi.

Richard Powell, author of Wabi Sabi Simple, tells us -"wabi-sabi nurtures all that is authentic, by acknowledging three simple realities: nothing lasts, nothing is finished, and nothing is perfect", and that imperfections are to be appreciated as part of life. 

Imperfections in fact, within a craft such as dry stone walling, can create works that actually exceed the level of 'correctness' we were striving for.

They (imperfections) may not just have to be 'accepted', but in fact be anticipated, as making the perfection of the thing seem very close

In the process of trying to build the temple we tried to embrace this idea as we strived (and yet more importantly 'chilled' ) about the perceived allowable tolerances that were needed to attain a certain aesthetic perfection. In the process we saw a wonderful thing happening. A kind of self-fulfilling happenstance. Combinations of self-cancelling discrepancies 'happened' enough times that we almost came to expect them.

It was this aspect of the temple building that led us to come up with the name. At first I suggested it be called - The temple of Imperfection (singular) but Sean said that wasn't quite right. (it was imperfect? )  The temple, however, with all our hard work measuring, cutting and fitting, was not completely imperfect. If anything it was incompletely perfect, (ie. made up of lots of imperfections). And so we agreed to call it the Temple of Imperfections.

Sean Adcock measuring and remeasuring and allowing for imperfection

And here I venture into the second wabi-sabi principle. The reality that in life, nothing is complete. Nothing in the universe including  'creation', and  'creativity',  is finished!  

This would seem true of the build we started at the Stonezone, in California , in 2019, as the project has been spread over a period of four years, with building sessions lasting three or four weeks each year, so far.  And, here's the thing - it still isn't finished. There is so much waiting to be done, yet. 

But it certainly looks finished.  Is this just happenstance? The thing that has certainly happened , has become and is becoming, an accumulation of 'incompletenesses'  ( word ?) and yet in a very real way it has attained a feeling of completeness.

The third reality of the temple (and in wabi-sabi) is that everything is impermanent. Even though we are working with what is essentially permeant stone material, granite, mica schist, basalt  sandstone and marble, and we know that it is not going to last. But for all extensive purposes it will outlast (outlive?) a lot of other things. And here's the thing. It will outlast all our impermanence.  

Those of us who worked and continue to work on the temple are temporal. We wallers and masons and sculptors have gathered together as a dedicated group of impermanent mortals. And yet all our accumulative impermanences have ironically created something very lasting.

Again the three principles of Wabi Sabi are - nothing is perfect, nothing is completely finished, and nothing is permanent somehow accommodate our understanding of the essence of the temple.   It could have been called the Temple of Wabi-Sabi because the structure exists as a kind of accumulation of the realities of life -Imperfection, Incompleteness, Impermanence. And if the universe embraces these three naturally occurring, what shall we call them, limitations? ironies? conundrums? discrepancies?...  then so do we! 

My hope is that the temple, may, with its myriad of discrepancies, given time, and skill, (if they don't already, eventually) all cancel each other and create a very satisfyingly balanced result.  

 

Consistent Imperfections- The Inside Quoins

Sean goes on more.. .   "The inside quoins were another matter.  At any point up the wall the batter is different, as it curves in or out the radius of the circle and hence the face changes, in addition the curve on the top and bottom of the stone would have different radii.  Basically no two quoins were going to be the same.   For it to work, I felt the key was to try and mark everything accurately as close to perfect as possible and then the inevitable  imperfections would not matter.  Several curbs (heritage dressed granite stone, salvaged from the streets of old San Francisco) were cut to give a stock of various thicknesses/lengths, to allow for a choice when fitting (and as they were much thinner than the outside quoins, for me to work out all the possible combinations to get to a level to match the outside for the throughs).  Whilst fairly regular, the kerbs were not machined, and so additional ones were also made to order later.  

With runners (ie set along the curve) the first step was to offer the quoin up and mark the inside edge so it could be cut to the correct angle allowing for the 2 ends of the face to be just outside the line of the curve for waste to be chiselled off.  Stretchers (running into the doorway) were easier as the long edge was just run along the inside face of the doorway/opening. The quoin was placed on the wall, the profile was placed against either end and the curved batter marked on the stone with a pencil.  The bottom edge was marked by running the pencil along the stone it was sitting on.  The curve along the top length was then marked by eye (ie approximated- the posh version of ‘guessed’) the important thing was that it didn’t scallop sharply or be too straight either - provided it was only slightly imperfect to the eye it would work.  I often drew a straight line joining the marks of the curved ends, and marked the centre of this, I could then see a lot easier if my freehand curve line was too asymmetric, since I could see the offset relative to the straight line.  

The inside end was far harder to mark than the exposed end with stones getting in the way of the frame, I’m not sure I can explain that fully or even remember why!  However I do remember the exposed end…

 

The key was to get the batter curve  very accurate at the exposed end.  In reality we realized from the outset that it was unlikely any face was going to be truly perfect with all the curves involved but the only really visible bit that would catch the eye was that exposed end.   I also felt it was important that one person…which happened to be me 😊 was responsible for all the marking, as to a degree, it needed a consistent approach and some of it was approximated - if one person was doing it, it was more likely that the imperfections would at least be reasonably consistent.   One thing we did not need was imperfect imperfections!  The net result was that I sometimes felt I was monopolizing the fitting, but on the flip side if I’d been chiselling we’d probably still be there now.  

Fabrication of these quoins prove heroic I think,  we had plenty of material. My exhortations were less plaintive just pointing out which was the crucial curved end.  <<Wish I could remember how mark described the stone - chiselling sugar or something>> Probably one in six went wrong and a corner blew or the stone cracked.  I had meant to make at least one quoin and I sometimes regret that I never got around to making even one of them, subliminally the distant curses probably had an effect."

Quoin Recollections

Sean Adcock goes on to explain about the quoins in the temple... 

"The outside quoins ( corner stones ) were relatively simple, in as much as anything was simple in this build.  There was a lovely group of sawn white granite lengths on site, which we requisitioned amongst some stiff competition ( wanted for some 'lesser' use it in a rival installation ) if I remember correctly. 

Whilst it was sawn and fairly regular the stones weren’t uniform. They were a variety of sizes varying  an inch or two between themselves, and some variation within, one or two were tapered.  So there was much measuring and checking to ensure we could get groups of 4, more or less the same, so that the doors would be just about symmetrical, not to mention finishing at the same height.  

It was going to be a shame to cut up the lengths, but it would give us a good start, and we thought, look very clean and precise.  As it turned out we could get enough. The least regular of the chunks could be adjusted (ground down) to make the final quoins, just below the springers, at around our envisaged height of 72” for both doors.  There was even enough to make 2 pairs of tie stones.  The major worry with these quoins was that there was not enough material for spares (or any mistakes?).  If I had miscalculated, if a chisel went astray, if a corner spalled ! 

 

The blocks were carefully cut square leaving an original cut edge for the inside of the door.  The face was then marked for a batter of 1:10  - millimetres again coming to the fore … if the stone was say 255mm tall then the offset at the top was 25.5mm more, the face was marked at 10mm at base an 35.5mm at the top on the two ends, the marks joined top side and bottom- joining the dots again – and handed over to John, Mark et Al to perform their chiselly magic, (which included dressing the outside faces of each stone)

I have always respected  their abilities with a hammer and chisel, something I have little experience of,  I am sure they got fed up with my “be careful”s, “don’t chip the corners” entreaties.  They tell me it was a friendly stone to work, whatever my views of them changed from respect to envy.  No room for error, and there was none, not even with my measuring (little did they realize what a novelty this is – the porch in my house has a very posh window which I originally measured for an upstairs bedroom, the porch ended up being built to fit the window that didn’t fit in the bedroom… enough said.

Interestingly the decision to have clean tight fitting quoins here dictated much of the build of these temple doors.The mica schist used in the walls had to be carefully chosen and often cut to fit buttes to the corners, so that it too was relatively tight, and then the voussoirs too needed to be as precise as the quoins in order to not look incongruous."

(The treatment of the third door opening in the temple was a bit different from the other two, and the story of that will be told  later.

The Internal Batter

The lean of the outer wall of our design would have the typical batter of a dry stone wall. However, for the batter of the inner wall of the hexagonal temple, we decided to create a gradual concave curve that would come to vertical above the point it started from at 8 feet, with a maximum offset/deflection  of 6 inches, something subtle so visitors wouldnt necessarily notice straight away, so as to  not be immediately obvious.

Sean thought the best approach was to make a ‘profile’ or ‘template’ which could be used at any height to check the batter curves evenly.

This profile would in effect be part an arc, that is part of the circumference of a larger circle. 

 

Sean writes, “ Given it was an arc, the height was in effect a chord (8 feet) and given the known offset (6 inches) I was able to calculate the radius of the imaginary circle our arc would be taken from.  Then taking the edge of a sheet of plywood as a tangent to the centre of our arc,  I was able to calculate the distance of the arc from the tangent, via trigonometry and very possibly witchcraft… I can’t actually remember exactly what I did, and I have lost my original diagram, with calculations on it, I did however at the time transfer the computed measurements to a notebook, in case the notes got lost/damaged and we needed a new profile…  

To make my life easier I had converted everything into centimetres and gone for offset of 15cm and length/height of 240 cm (whilst imperial measurements of 64ths of an inch are more accurate than millimetres but using a calculator and having decimals makes metric more user friendly  - you don’t need to recalculate 9.82(cm) into inches and sixty fourths). I marked the offsets on the ply, every 2cm I think , where the change was noticeable, every 4cm where the change was minimal (ie towards top the bottom) and literally joined the dots. I handed the plywood over to JSR to cut with a skill saw along the marked line, as I didn’t trust myself. A straight batten was then attached to the cut plywood, parallel to the straight edge, to strengthen it and give a flat edge against which a level could be placed.  

 

We had marked the centre of the floor to give scribe internal circle footprint and carefully ran the first course of interior stones, using a wire from the centre point. Then placing the profile against the base of the wall and ensuring it was vertical and the surface plane pointed towards the centre of the circle , and thus  theoretically give the correct position for a stone at any point in (and up) the wall.  

This was of course not entirely true as straight stones don’t sit exactly on a curve, as , in an inside curve, only the centre of the stone is on the correct line, so care had to be taken to remember this for the first few courses before a more uniform curve was in effect created against which the profile could be ‘rested’. Even then stones occasionally got in the way, the surface was full of imperfections.

 

It had been clear for some time that our build would go beyond the maximum height of the profile we were planning to use,  and an extension would be needed.  I can’t remember if JSR or I suggested exaggerating this last bit of curve before building up to the upper ‘rim’ , in order to emphasize the subtlety of the original curve, and to really start bringing the upper ridge more towards the centre, to create an overhang  above people’s heads.  It was one of those many things that we had apparently both been mulling over, so that when one of us suggested it the other said ‘yes I was thinking that…’  Anyway I came up with a curve I thought transitioned well, and wouldn’t be entirely lost with the thickness of stone we were working with.

Wet Dry Walling

 

Before we go into all the details of the temple's arch dimensions, the exterior batter and vertical elliptical interior walls, and all the niche arrangements, the types of stones we used and how they were measured and shaped, I think we should pause and just look at how wet dry stone walling can be. This was the rain of the not so rainy season that California sorely needed, but we didn’t.  It’s always a trade off. 

               

Walling is fun in the rain, sometimes. But when it involves really precision work and electric grinders and gas powered cut off saws , it can loose its appeal. The carefully drawn lines chalk lines and scribed coloured pencil marks on the stones all disappear in a dusty soupy mix. The grinder extension wires short out in the puddles. You are always losing your chisel in the mud. Your soggy tape measure jams up. The hand carts loaded with heavy cornerstones sink up to the axles. And of course everything is super slippery.

But we poured on , I mean powered on, hoping to see a rainbow.

And Lo...  On the third day we saw the light of the sun.

Basalt of the Earth.

Basalt Columns look manmade. They look like they are trying to look like a lot of work went into carving them. They are just asking to be stood upright , and to be used like bookends where dry stone walls start and end . And why not?  They work.

We’ve used them in a number of stone art installations and I’ve used them creatively in workshop projects too. 

Here we used three columns as bookends in this triangular three style wall workshop at Lygso Stone Supply in Redwood city 

Here one shorter basalt served as a middle column for a double arch workshop I did with beginners. 

This ‘test wall’ we created back in 2015 between two trees was successful enough that we reconfigured it in a second project using basalt columns to substitute for trees.

Imagine that ! Basalt stone, not just looking manmade but pretending to be trees too. 

However instead of designing a project with basalt columns at ends of walls, I thought why not have them holding the corners of a structure connecting six walls making a hexagonal shape. 

The columns would have the strength and mass and weight to do the job, and give it a beautiful manmade architectural look

In any case, making six conventional cheekend hexagonal wall corners with just mica schist material, (which was what we planned to use on the bulk of the hexagonal temple), would have been very difficult to do, and we would end up having corners with very weak bonds. So that's where we lean on the basalt to come to the rescue. 

We just stood the columns up on end and then began to build/butt our six walls up to them. Voila!

And by the way, the man behind the very difficult job of cutting all six of the columns perfectly square enough at the bottom, so that they would stand on the pad absolutely upright and steady, without any rods or fasteners, was our man on the scene Shawn Kelly. Good job there Kelly

The point is its not difficult to find ways to accommodate such accommodating material into the dry stone mix.. And that's what we did in designing the six- sided temple.

Except now, the design had changed somewhat. 

But that's for another blog entry.

And so began the next stage of the temple with no name yet.

 

Our New Hexagonal Pad

Our plan to build it there at the crossroads changed when our patron client crane operator and heavy material transporter informed us it would be too tricky to attempt to build a structure of that size in such a difficult place to get to. Plus the rains were coming and the stagecoach road would become a big mud slide. 

So we explored other options on the property and came up with a great one. The top of a prominent hill. Good access. Highly visible. And a nice veiw through the trees from the northern approach . 

And so began our laying down of the base line of our hexagonal  rock temple.  It had several other names back then but nothing was sticking yet.

Our plan was to measure everything carefully and create a six inch thick reinforced hexagonal concrete pad to build our structure on. (I was outvoted on building it without a pad.)

So Mark Ricard, Shawn Kelly, Sean Adcock and I set about forming it in, raking in the gravel, putting in the rebar, and spreading and levelling the concrete when it arrived.

It looks dazzling don't you think?

Sean stood holding makeshift upright concrete tools either side of him, to imagine the size of and where the first arched opening was supposed to go, and to get a sense of proper proportion. We had no idea how many Brenda's high it would be. 

From here on, we would be building everything else with natural stone . No devil's cream, or any of that horrible Devil's Porridge!

 

 

The Y Intersection

The original plan involved being invited to think about what we might be able to do in the way of a new stone installation, to be positioned in a more remote part of a property in an area of California we now affectionately call the StoneZone . This time it would be directly in the middle of the Y intersection created by the Old Stagecoach Road (running east and west) and a newly cleared track that forked off to right (northwest). The idea was that whatever it was, could be seen from three directions. The flatfish area was flanked with abrupt changes in elevation and trees and bushes which meant that anything we built there would likely be seen only if you were approaching from one of the three directions.

I had previously dreamed of an idea of one day doing a six-sided six-arched dry stone structure and had drawn several sketches of it and developed it more on the computer. The design seemed like it could be adapted to still have six sides, but instead, have only three arches, all three facing the three roads, and the other three, no-road sides, be solid walls. 

The idea took. And in January of 2019 we started laying out the optimum dimensions and staking out the six corners. Imagining the structure inside this new intersecting space seemed a bit contrived, even though it was exciting to be considering being able to create something in such a standalone site, with no other existing structures around it, competing for the view.

As we measured and tried different angles to get the thing aligned to the roads, Sean Adcock and I realized the three arches could not each be evenly separated. The asymmetry of the Y shape created by the skewed angle of the three road directions, meant that the building would have to have two adjoining arched sides and then two adjoining solid wall sides and then one lone arch and then a lone solid side. 

And still, it didn’t look like. I wonder why.

 

Go Configure !

 I probably should tell you right away that I don’t know why we built the Temple of Imperfections. I know how the concept came about, and what we thought it would involve, and what it would likely look like,  and even conjectured on what it might mean and what impression it might give, and yet I still have no understanding of the ‘why’ of it. Why DID we build it? I could make up something about configurations and alignments that made it have some special purpose in planning of planting crops or something to do with fertility rites. But I won't. 

I rather console myself that there are likely many things, built of stone, long lasting things, some of them very massive structures , some very difficult to erect, dotted all over this ancient globe, which were painstakingly built with tons of men and many many more tons of stone, built by people like me and you, who really had no idea what they were doing, not because they were unskilled, but because they had absolutely no concept of why they were doing it. 

I imagine Stonehenge to be in this category. The people who came together to build this mysterious configuration of huge standing stones, likely stood back themselves when they were done and wondered what it was actually for, and pondered to understand why exactly they had built it. Thankfully they built it with a material durable enough to last ages and ages, so that it would allow enough time for someone in some future more ‘advanced’ culture to unlock the essential cause for its having been made. 

Likely any of the builders back then , who were asked the question "Why was it built?", would have had to answer, ‘because’.  And so we join with our stone brothers and sisters of the past, and say “ until the mystery of why we did it, is revealed to any of us, we can only scratch our heads and answer, "Well..mostly, just because !"

( More of the story of how, where, when, what, and who to follow )