Showing posts with label medieval construction. Show all posts
Showing posts with label medieval construction. Show all posts

Tuesday, April 19, 2022

The geometrical design of Harmondsworth Great Barn, Laurie Smith

For Laurie Smith, my friend

 

 Here are the front and back covers of Laurie Smith's last book.

 

 

 

The book is full of beautiful photographs of medieval framing  and the history of the conception and construction of these barns' frames - from felling the trees to placing the aisle braces. 

 


 

 

 

Of course, as the book is about Geometrical Design, it's also is full of daisy wheels and explanations of how they were used to design the Harmondsworth Great Barn. 
Laurie Smith was a Geometer, probably the best. He researched, wrote, and taught architectural (aka 'practical') geometry.  His language and his drawings are clear and engaging. 

 

 

 

It is a book to read, think about, study. It can be read by a novice as well as one well versed in geometric construction. Laurie's first Drawing 1 is titled: "Names and Locations of the Frame's Timbers". It's accompanied by a Chart: "Heavy timbers needed for the barn's section". From that basic introduction he explains the geometry of the barn. 

 

 

If at Photograph 39 you aren't sure what an 'arcade post' is, that first drawing is readily available. Using Photograph 39 Laurie explains how - with simple drawings, photographs, and the language of timber framing -  arcade posts, arcade plate jowls and buttresses fit together and why they are important. 

Then you understand Drawing 54.


 


 

Laurie doesn't just quote Vitruvius. He  spends time with those terse sentences in Book I, De Architectura, exploring as a Geometer, whose tools are a compass and rule, what Vitruvius means when he writes a "...plan is made by the proper successive use of compasses and rule". 

 

Laurie includes a carpenter's dividers, probably his own. He explains how they are 16.5 inches long, proportional to a rod which is 16.5 ft., and discusses 'stepping off'.

 

The geometric analysis of other great barns - The Barley Barn, Cressing Temple, Essex, and the Leigh Court Barn, Leigh, Worcestershire - is thorough and clear. 

The Notes and Credits are good reading, not a perfunctory listing of people and books. There is much here to absorb, come back to, consider again. 

 

   

Laurie finished the text, the geometric drawings, and the design in the summer of 2021. It was published that fall by Historic Building Carpentry in partnership with the UK Carpenters' Fellowship.*

He sent me a copy. I read it twice and told him how much I liked it. At his request I sent copies to a few of the timber framers in the States who had worked with him . 

 

I wrote that I'd put a review on my blog as I had before for his book on a barn in Devon. Here's the cover of that book.

My review is: https://www.jgrarchitect.com/2020/11/architectural-geometry-rare-geometrical.html

We enjoyed seeing that over 700 people had read that review. (now over 800)
We wondered how many had found his website through my blog post. He listed my blog on his website. I hadn't yet figured out  how to list his on mine. 
We talked about the geometry we'd  explored and learned about in the last 8 years.


 

Then Laurie died, December 2, 2021.

Now it's hard to read his books. I want to send an email across The Pond , "Yes, and what about....?" 

Then I remember that I read Durer, Serlio, Palladio and feel that they are speaking to me directly, 500+ years later.  Like them, Laurie's spirit is in his book. His words share his awe, his joy, and profound understanding of the geometry he saw, knew so well, and loved. 


*The Geometrical Design of the Harmondsworth Great Barn  is available through the Carpenters' Fellowship, ( https://carpentersfellowship.co.uk/) in the UK. I act as the distributor in the States. Please contact me if you would like a copy @ $25., including postage.




Sunday, January 17, 2021

Albrecht Durer's 'Melancholia' and his knowledge of construction and practical geometry

Note: click on any image to enlarge it!

Albrecht Durer was a painter and print maker in Germany, 1471-1528. He also wrote books, and traveled widely in western Europe. He was a superb draftsman. I have enjoyed the compositions, the details, and the lines in his engravings and woodcuts for 50 years.

His woodcuts were for the people, most of whom were  illiterate. Their livelihoods did not require writing. They could read the images: here the rough stable, the well dressed men coming to see a baby, the angels and the star. 

The engravings were not so easy to make. They were for books, for people who could read.


These plates come from the Dover Publications reprints of Durer's wood cuts and engravings.* This is print #183.

 

 

He drew what he saw around him. His plates are full of the life he knew, including construction details. 


This detail from #183 shows a truss which includes a collar tie with angled tenon joints and pegs. The purlins and rafters are structurally correct.

 

 


The detail from Plate #190, shows the grain of the wood brace running in the right direction. The angled cuts for the joints could serve as templates for repair.

     

    Here in Plate #185, the brace is tied. a peg serves to tighten the tie as needed. The thatch for the roof is properly applied.


    When I began to write this post I was thinking about Durer's knowledge of construction and his use of geometry in his compositions. (More about that in another post.)
    I was side tracked as I began to read Durer biographies. The scholars who wrote them rarely knew about construction. To them the structures are allegories or useful for his compositions. 
    I saw practical and abstract geometry.
    This is my exploration, as a Geometer, of one of  Durer's most important engravings.

     
     
    'Melancholia', Durer's engraving about the temperament of  artists and  artisans, was made in 1514.*  

    Durer put many construction tools around his melancholy angel. She holds a compass.  Tucked beside her hand is a gauge. The putto sits on a mill wheel next to a ladder. Set beside the polyhedron is a pot for hot liquid metal, possibly lead, on a brazier. Under the angel's skirts is a pair of pliers.

    The tools are used in practical geometry. Above the dog is a hammer. Between his front legs and the sphere: a Line and its plumb bob.

    In the lower left corner is a profile gauge.

    Then: a plane, a saw, and a straight edge that can be used to draw arcs. It may also be a level.

    Lastly: nails and a nail punch.

    The theory was that Melancholy, influenced by the planet Saturn, was part of the inherent character of artistic and philosophical people. There were 3 levels. The lowest was artists and artisans. The next was scholars, natural scientists, and statesmen. The highest level was theologians and those who studied the secrets of the divine.
    Here the putto is taking a nap after doing some numbers (perhaps) on a slate, the lowest level. The angel, on the other hand, is intently studying the polyhedron, an abstract shape. She is a scientist. The dog  - which I learned represents 'faithfulness' - is waiting. The sphere is an abstraction, perfect as the tools and mill wheel are not. They are all 'things', 

     

    The scales, the hour glass, the bell are said to refer to the knowledge of artisans: they understand weight, measure (of time), music (as an expression of geometry). 

     

    I have very little understanding of the Magic Square. I do know that all the lines add up to 34 and no number is used twice.

    I do wonder if in a largely illiterate society, the fairly recent acceptance of Hindu-Arabic numbers, as opposed to Roman Numerals, might be part of its purpose here: to illustrate the scholarship, the mathematics that numbers made possible.

    Try substituting Roman Numerals in the grid of the Square.
    Can you quickly add up the amounts? How would you do it as an arithmetic problem on paper? 

     16 +5+9+4 = XVI+V+IX+IV .

     

    I will write about the polyhedron in the next post. 

     

    *images from  The Complete Woodcuts of Albretch Durer, edited by Dr. Willi Kurth, 1963  and The Complete Engravings, Etchings & Drypoints of Albrecht Durer, edited by Walter L Strauss, 1972.  Both republished by Dover Publications: www.dovderpublications. com.

    Walter L. Strauss' analysis is the best I've found. I wish he had known more about geometry.