{"id":122,"date":"2020-05-19T21:21:01","date_gmt":"2020-05-19T21:21:01","guid":{"rendered":"http:\/\/vpcathedral.chass.ncsu.edu\/?page_id=122"},"modified":"2023-07-13T14:32:39","modified_gmt":"2023-07-13T18:32:39","slug":"constructing-the-visual-model","status":"publish","type":"page","link":"https:\/\/vpcathedral.chass.ncsu.edu\/?page_id=122","title":{"rendered":"Constructing the Visual Model"},"content":{"rendered":"
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St Paul’s Cathedral, the Visual Model<\/em>.<\/strong> Rendered by Austin Corriher.<\/figcaption><\/figure>\n<\/div>\n\n\n

Goals for the Visual Model<\/p>\n\n\n\n

Our goals for creating the visual models of St Paul\u2019s Cathedral and the buildings surrounding it in Paul\u2019s Churchyard have been to achieve the highest possible degree of accuracy and authenticity in our work. Nonetheless, due to gaps in the evidence, we have had, from time to time, to infer various aspects of our models from the data we have or \u2014 when only minimal data is available \u2014 to use models representative of the genre or type of building we know or believe to have been in that spot.<\/p>\n\n\n\n

One way of thinking about the visual model is to imagine it as an exercise in data visualization, not unlike a pie chart or a bar graph. In this case, however, the number and kinds of sources, their relative accuracy and authenticity, and their incorporation of nonrepresentational conventions of display exceed significantly the number of variables usually integrated in conventional data visualizations.<\/p>\n\n\n

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Scale Drawing of the Foundation of Paul\u2019s Cross. From Penrose, \u201cOn the Recent Discoveries of Portions of Old St Paul\u2019s Cathedral, Archaeologica<\/em> 47 (1883), 381-92<\/strong><\/figcaption><\/figure>\n<\/div>\n\n\n

A good bit of information survives from pre-Great Fire London to help us achieve that goal. Unfortunately, the data we have is often partial, fragmentary, contradictory, or imcomplete. On a number of occasions, we have had to fill in missing portions of the data with what we hope to be informed guesses.<\/p>\n\n\n\n

A good example of this is our model of the Paul\u2019s Cross preaching station, visible on the website of the Virtual Paul\u2019s Cross Project<\/a>. Thanks to the work of Francis Penrose, Surveyor to the Fabric of St Paul\u2019s in the late 19th century, we know with high accuracy the size of the base of the structure.<\/p>\n\n\n\n

Penrose excavated the foundations of Paul\u2019s Cross and published his findings. To read Penrose\u2019s full account of his survey of the Paul\u2019s Cross<\/strong> foundations, go here: Penrose Archaeologia (1883)<\/a><\/p>\n\n\n\n

Penrose\u2019s measurements only give us a design for the base of the structure and a sense of its overall scale. To move upward from the base, we turn to images of Paul\u2019s Cross that survive from the early modern period. Although they differ in many details, they give us a pretty good general idea of what it looked like.<\/p>\n\n\n\n

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Pau’s Cross, 16th Century Engraving. Image courtesy Wikimedia Commons<\/figcaption><\/figure>\n<\/div><\/div><\/div>\n<\/div>\n\n\n\n
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Paul’s Cross, 16th Century Drawing. Image courtesy Pepys Library, Magdalen College, Cambridge<\/figcaption><\/figure>\n<\/div><\/div>\n<\/div>\n\n\n\n
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John Gipkin, Paul\u2019s Cross (1616). Image courtesy of the Bridgeman Art Library, New York, and the Society of Antiquaries, London.<\/strong><\/figcaption><\/figure>\n<\/div>\n\n
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Paul’s Cross, 16th Century Engraving. Image
courtesy Wikimedia Commons. <\/figcaption><\/figure>\n<\/div><\/div>\n<\/div>\n\n\n\n

What we don\u2019t know, however, is the height of the building. The height we finally decided on is based on an assessment of the overall structure with regard for proportion, overall scale, and a sense of what height was needed for the structure to function comfortably as a setting for a two-hour-long event.<\/p>\n\n\n

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Paul’s Cross, the Cathedral Project. <\/em><\/strong>From the Visual Model, rendered by Austin Corriher. <\/figcaption><\/figure>\n<\/div>\n\n
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Paul’s Cross, the Paul’s Cross Project.<\/em><\/strong> From the Visual Model, rendered by Jorday Gray. <\/figcaption><\/figure>\n<\/div>\n\n\n

The models of buildings one sees on this website embody data that exhibit a range of levels and types of accuracy, of specificity or general categorization, of levels and types of accuracy. Images shown on this site reflect decisions that easily could have resulted in different images altogether. <\/p>\n\n\n\n

Our models are, therefore, at best a mixture of hard data, inferences, and approximations of the objects and spaces they recreate. We use them best when we recognize that they are not mirror images of reality but tools for interpreting their subjects, as important for what separates them as they are for what links them to their subjects.<\/p>\n\n\n\n

As this discussion suggests, the data we have available, while considerable, does not provide everything we need to know to produce a completely data-driven model. Although everything one sees in our model is based on a careful consideration of the historic record, there remain gaps to close, conflicting evidence to evaluate, choices to make, assumptions to ponder and question.<\/p>\n\n\n\n

The models of buildings one sees on this website embody data that exhibit a range of levels and types of accuracy, of specificity or general categorization, of levels and types of accuracy. Images shown on this site reflect decisions that easily could have resulted in different images altogether.  <\/p>\n\n\n\n

We can sort the kinds of data available to us into the following categories:<\/strong><\/p>\n\n\n\n

1. Data-based accuracy<\/strong> \u2014 information that is accurate in the sense that it is based on actual measurements, like measurements of the cathedral\u2019s foundations<\/p>\n\n\n\n

2. Historic accuracy<\/strong> \u2014 information that comes to us from the historic visual record, which is only as good as the image is accurate. After all, Hollar\u2019s drawings do not always agree with his engravings. Which should we follow, if we have both?<\/p>\n\n\n\n

3. Representational accuracy<\/strong> \u2014 when, as is the case for many of the buildings in the Churchyard, we have the measurements of the foundations of the building, and maybe a detail or two about the number of stories or number of garrets, but no further details. But we know from other evidence what kind of building it was, and we know what features buildings of that kind had, so we can create a representation of that kind of building based on other buildings of that kind for which we have images or can look at surviving examples.<\/p>\n\n\n\n

4. Informed guesswork<\/strong> \u2014 what we do when we know some things, but not others, so we have to make a guess about the missing details.<\/p>\n\n\n

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St Paul’s Cathedral, the Cross Yard. From the Visual Model, rendered by Austin Corriher. <\/figcaption><\/figure>\n<\/div>\n\n\n

Modeling the Cathedral — the Exterior Model<\/p>\n\n\n\n

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We started our modeling literally from the ground up. The Cathedral\u2019s original foundations partly survive in the ground atop Ludgate Hill. They have been surveyed by archaeologists who have determined with a very high degree of accuracy the basic shapes and dimensions of the structure\u2019s foundations.<\/p>\n\n\n

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Paul\u2019s Churchyard, c. 1500. From John Schofield, St Paul\u2019s Cathedral Before Wren<\/em> (2011).<\/figcaption><\/figure>\n<\/div>\n\n\n

John Schofield, St Paul’s archaeologist, has gathered all this data into his monumental study St Paul’s Cathedral Before Wren<\/em><\/strong> (English Heritage, 2011), a volume absolutely essential to our work. From Schofield’s work, we have derived the basic floorplan for the Cathedral, the basic measurements of the buildings and the space around them, and the basic geometry of the Churchyard itself.[1]<\/sup><\/a>For a discussion of the design and construction of St Paul’s in the context of other English and continental cathedrals, see Christopher Wilson, The Gothic Cathedral<\/em> (London, 1990).<\/span><\/span>