It was shown in WTC1 Accurate Collapse Mappings that features of the initial failure sequence can be understood as a rapid succession of 11 identifiable events occurring in the following order:
1) Deformations: Inward bowing of the south face
2) Inward bowing on the north face
3) Earliest detectable creep movement of the antenna and northwest corner
4) Appearance of ~87th fl S face ejections
5) Appearance of 95th fl W face ejection
6) Visible downward movement begins: Concave deformation of the roofline, antenna drops before north or west perimeter walls
7) Columns fail over tilt of less than 1 degree, appearance of 98th fl ejections and 105th floor ejections
8) Appearance of 77th fl W face ejections
9 ) Splitting of all perimeter walls: All visible upper parts fall out and over lower parts
10 ) Southward sliding of upper portion
11) Dis-integration of upper portion
What people see as the beginning of visible downward movement is marked blue.
All claims are verifiable and all methods are reproducible.
The NIST failed to notice items 2,3,4,5. They completely misrepresent items 6 and 7, with tilt measurements off by more than 800%. They failed to notice or mention items 8, 9, 10 and 11.
In this section the NIST descriptions of WTC1 early motion are examined to see how well they understood this same sequence of events.
NIST's KEY OBSERVABLES: NIST MEASUREMENT AND MAPPING OF EARLY MOVEMENT AND THE COLLAPSE INITIATION SEQUENCE
The NIST lists its key observations of the early movement of WTC1 and WTC2 within NCSTAR 1-6 and 1-6D.
NCSTAR 1-6 is linked here
NCSTAR 1-6D is linked here
All descriptions of early movement of WTC1 within NCSTAR 1-6D are quoted below. The descriptions of early movement of WTC2 are also listed so as to compare how the NIST understood the early movement of each tower in relation to the other.
It should be clear from the quotes that the NIST considered WTC1 to lean and move in a very similar way to WTC2, tilting about the same amount as WTC2 as the columns fail throughout the building before the upper portion begins to fall vertically.
WTC1:
"First exterior sign of collapse was at floor 98. Rotation of at least 8 degrees to the south occurred before the building section began to fall vertically under gravity."
-xliv
Comparison with the description of WTC2:
"Tilt of approximately 3 to 4 degrees to the south and 7 to 8 degrees to the east occurred before building section fell."
- page xliv
According to the NIST, WTC1 rotated as much to the south before falling vertically as WTC2 tilted to the east. Every description and comparison with WTC2 within the NIST reports makes the same claim as can be easily seen in the collected body of quotes.
........................
WTC1:
"The section of the building above the impact zone tilted to the south (observed at about 8 degrees) as column instability progressed rapidly from the south wall along the adjacent east and west walls (see figure E-11), resulting in increased gravity load on the core columns."
- page liv
(fig E-11 is the same as fig 5-8 shown below)
Comparison to description of WTC2:
"The section of the building above the impact zone tilted to the east and south (observed at about 7 to 8 degrees to the east and about 3 or 4 degrees to the south, Fig. E-16) as column instability progressed from the east wall to the adjacent south and north walls."
-page lviii
......................
WTC1:
"First exterior sign of collapse was at floor 98. Rotation of at least 8 degrees to the south occurred before the building section began to fall vertically under gravity."
- p 312
Comparison with the description of WTC2:
"tilt of approximately 3 to 4 degrees to the south and 7 to 8 degrees to the east occurred before building section fell."
- page 319
...................
" The section of the building above the impact zone began tilting to the south (observed at 8 degrees, table 5-2) as column instability progressed rapidly from the south wall along the adjacent east and west walls (see fig 5-8) resulting in increased gravity load on the core columns. The change in potential energy due to downward movement of building mass above the buckled columns exceeded the strain energy that could have been absorbed by the structure. Global collapse ensued.”
- p 314
Figure 5-8 is shown below.
Fig 2.31 A reproduction of NIST NCSTAR 1-6D fig 5-8, misrepresents WTC1 as leaning from 0 to 8 degrees as columns failed from south to north. In reality, the building leaned less than 1 degree and had multiple signs of early core failure over the original column failure sequence, as demonstrated in this section.
Comparison with the description of WTC2:
"The section of the building above the impact zone tilted to the east and south (observed at about 3 to 4 degrees to the east and about 7 to 8 degrees to the south, Fig. 5-16) as column instability progressed from the east wall to the adjacent north and south walls. The change in potential energy due to downward movement of building mass above the buckled columns exceeded the strain energy that could have been absorbed by the structure. Global collapse ensued."
-page 321
..............
All references to the early movement of WTC1 during collapse initiation from NIST NCSTAR 1-6 are listed below.
.................
WTC1:
"The WTC 1 building section above the impact and fire area tilted to the south as the structural collapse initiated, as shown in Fig. E-6. A tilt to the south of at least 8 degrees occurred before dust clouds obscured the view and the building section began to fall downward."
-page liv
comparison to the WTC2 description:
"The building section above the impact and fire area tilted to the east and south as the structural collapse initiated as shown in fig. E-8. There was approximately a 3 to 4 degree tilt to the south and a 7 to 8 degree tilt to the east prior to significant downward movement of the upper section".
- page liv
.........................
WTC1:
"The entire section of the building above the impact zone began tilting as a rigid block (all four faces, not only the bowed and buckled south face0 to the south (at least about 8 degrees) as column instability progressed rapidly from the south wall along the adjacent east and west walls."
- page lxviii
comparison to the WTC2 description:
"The entire section of the building above the impact zone began tilting as a rigid block (all four faces, not only the bowed and buckled east face) to the east (about 7 to 8 degrees) and south (about 3 to 4 degrees) as column instability progressed rapidly from the east wall along the adjacent north and south walls. The building section above the impact continued to rotate to the east as it began to fall downward and rotated to at least 20 to 25 degrees."
"A tilt to the south of at least 8 degrees occurred before dust clouds obscured the view and the building section began to fall downwards."
- page lxxv
Comparison to the WTC2 description:
"Estimates made from photographs indicate that there was approximately a 3 degree to 4 degree tilt to the south and a 7 degree to 8 degree tilt to the east, prior to significant downward movement of the upper portion of the building"
-lxxvi
................................
WTC1:
"A tilt to the south of at least 8 degrees occurred before dust clouds obscured the view and the building section began to fall downwards."
- page 155
Comparison to the WTC2 description:
"Estimates from photographs indicated that there was approximately a 3 to 4 degree tilt to the south and a 7 to 8 degree tilt to the east prior to significant downward movement of the upper building section."
- page 167
...
.................
"Rotation of the building section above the impact and fire zone to at least 8 degrees to the south occurred before the building section began to fall vertically."
-page 156
Comparison to the WTC2 description:
"Rotation of approximately 4 to 5 degrees to the south and 20 to 25 degrees to the east occurred before the building section begins to fall vertically."
- page 169
......................................
WTC1:
"Rotation of at least 8 degrees to the south occurred before the building section began to fall vertically under gravity."
-page 298
Comparison to the WTC2 description:
"Rotation of approximately 4 to 5 degrees to the south and 20 to 25 degrees to the east occurred before the building section began to fall vertically."
- page 306
'''''''''''''''''''
"The entire section of the building above the impact zone began tilting as a rigid block (all four faces, not only the bowed and buckled south face) to the south (at least 8 degrees) as column instability progressed rapidly from the south wall along the adjacent east and west walls"
-page 300
Comparison to the WTC2 description:
"The entire section of the building above the impact zone began tilting as a rigid block (all four faces; not only the bowed and buckled east face) to the east (about 7 to 8 degrees) and south (about 3 to 4 degrees) as column instability progressed rapidly from the east wall along the adjacent north and south walls."
- page 308 and again on page 309
....................
"The section of the building above the impact zone began tilting to the south at least about 8 degrees as column instability progressed rapidly from the south wall along adjacent east and west walls, as shown in Fig. 9-13."
- page 304
Comparison to the WTC2 description:
>>>>>>>>>>>>>>>>>>>>>>>>..
The only descriptions of WTC1 early movement provided by the NIST are in NCSTAR 1-6, and NCSTAR 1-6D and are quoted here.
As anyone can verify from the comparison of the NIST WTC1 and WTC2 tilt descriptions in NCSTAR 1-6 and 1-6D, the NIST represents the tilt over which all columns originally fail as about 7 degrees to the east for WTC2 and about 8 degrees to the south for WTC1.
INDEPENDENT MAPPING AND MEASUREMENTS OF WTC1 BUILDING MOVEMENT THROUGH THE COLLAPSE INITIATION SEQUENCE BACK TO THE EARLIEST DETECTABLE MOVEMENT
As noted earlier as in section 2.4 it was shown that features of the initial failure sequence can be understood as a rapid succession of 11 identifiable events occurring in the following order:
1) Deformations: Inward bowing of the south face
2) Inward bowing on the north face
3) Earliest detectable creep movement of the antenna and northwest corner
4) Appearance of ~87th fl S face ejections
5) Appearance of 95th fl W face ejection
6) Visible downward movement begins: Concave deformation of the roofline, antenna drops before north or west perimeter walls
7) Columns fail over tilt of less than 1 degree, appearance of 98th fl ejections and 105th floor ejections
8) Appearance of 77th fl W face ejections
9 ) Splitting of all perimeter walls: All visible upper parts fall out and over lower parts
10 ) Southward sliding of upper portion
11) Dis-integration of upper portion
Within these observations are multiple indications of collective core failure. Not one of these observations is recognized within the NIST reports. The author could understand that the official reports could overlook an observation or two, but consider the multiple indications of collective core failure:
Inward boing of both south and north faces seen before collapse
Early antenna movement from 9.5 seconds before the collapse
Pull in of the NW corner from 9.5 seconds before the collapse
The upper portion of the south, west and north walls fail outside and over the lower portion
The upper portion detaches from the lower portion and slides southward at less than 1 degree tilt
There are multiple indicators of the same behavior.
Likewise, within these observations are multiple indications that the WTC1 collapse did not begin on the 98th floor as the NIST claims. The author could understand that the official reports could overlook an observation or two, but consider the multiple indications that the collapse did not begin on the 98th floor:
north face inward bowing along the 95th floor
87th floor south face overpressurization
95th floor west face overpressurization
Increased pressure along the 92nd floor west face
77th floor west face ejections
There is no need to speculate about these events since they are directly observable and captured in video and photographs, and therefore verifiable.
DETERMINATION OF TILT OVER WHICH ALL COLUMNS INITIALLY FAIL USING THE VISUAL RECORD
Review of the argument presented in section 2.4:
The columns fail from south to north and from east to west so the clearly visible NW corner would be the last columns to fail. The moment of failure is shown:
Fig 2.32 Visible failure of the northwest corner, the last group of columns to fail during the original failure sequence.
By synchronizing the video from the northeast, north, northwest and west views, one can determine the moment the northwest corner fails by visual inspection. It can be easily verified that the northwest corner had already failed in the frames shown below:
Fig 2.33 As seen from 4 different angles synchronized, this is the actual position of the upper section just as the last group of columns fail along the northwest corner. Note how visibly different each of the images are when compared to the NIST misrepresentations of the building leaning 8 degrees to the south.
A MORE PRECISE DETERMINATION OF TILT ANGLE
Anyone can determine tilt angles from various perspectives over which all columns fail by using a simple 4 step process:
1) Verify the west face fails from south to north:
2) Verify the north face fails from east to west:
3) Determine precise moment of failure of the northwest corner:
4) Measure tilt of antenna and other normally vertical features of the deforming structure from multiple angles at that moment
Steps 1 and 2 allow anyone to verify that the northwest corner is the last set of columns to fail. The precise moment of failure of the northwest corner can be determined by using the high resolution Sauret video and tracking the movement of the northwest corner:
Fig 2.34 A measurement of the vertical position (in blue) and the vertical velocity (in black) of the upper edge of the northwest corner during the initial column failure sequence. It can be clearl determined that the upper northwest corner starts to move downward at around 3.7 seconds as labeled on the graph.
The velocity curve in black allows the determination of the moment of failure of the NW corner with remarkable precision. One would naturally look at the point in which the velocity makes the initial sharp, downward transition. Both visual inspection and object tracking allow anyone to spot the moments of failure of the NW corner.
By synchronizing videos from other perspectives with the Sauret video from the north, tilt angles can be determined from each perspective.
VISUAL EVIDENCE CITED WITHIN THE NIST REPORTS TO SUPPORT THEIR CLAIMS
The following sequences of images from NIST NCSTAR 1-6 show the entirety of the visual evidence the NIST presents to support the claim that the building tilted 8 degrees as column failures propagated from south to north.
In the following sequence all columns had failed before the second and third photographs were taken even though the NIST misrepresents the failures as occurring during the sequence shown:
Fig 2.35 is a reproduction of NIST NCSTAR 1-6, figure 6-7 which shows how the NIST (mis)represents the movement of the building as the columns originally failed. The earliest visible ejections actually emerge from the 95 floor along the west face. The northwest corner, the last group of columns to fail, had already failed by the time the second and third images were taken.
Likewise, all columns had failed by the time the 2 photos below were taken:
Fig 2.36 is a reproduction of NIST NCSTAR 1-6, figure 6-9 which shows how the NIST (mis)represents the movement of the building as the columns originally failed. The northwest corner, the last group of columns to fail, had clearly failed by the time both of these images were taken.
Once again, all columns had clearly failed by the time the second and third photographs were taken:
Fig 2.37 is a reproduction of NIST NCSTAR 1-6, figure 6-10 which shows how the NIST (mis)represents the movement of the building as the columns originally failed. The northwest corner, the last group of columns to fail, had clearly failed by the time the second and third images were taken.
Once again, all columns had completely failed by the time the second photo was taken:
Fig 2.38 is a reproduction of NIST NCSTAR 1-6, figure 6-8 which shows how the NIST (mis)represents the movement of the building as the columns originally failed. The earliest visible ejections actually emerge from the 95 floor along the west face and are quite visible in video taken from this same viewing angle. The northwest corner, the last group of columns to fail, had already failed by the time the second and third images were taken. The entire upper section was moving downward in the second and third images as measurements of the upper northwest corner clearly show. At the time the second and third images were taken, there were forceful smoke expulsions from the 88th floor, south face, 10 stories below the claimed collapse initiation area along the 98th floor and from the 77th floor, west face, over 20 floors below the 98th floor smoke expulsions shown b the NIST within these images.
In the next case all columns had completely failed before all 3 photographs were taken:
Fig 2.39 is a reproduction of NIST NCSTAR 1-6, figure 6-11 which shows how the NIST (mis)represents the movement of the building as the columns originally failed. The northwest corner, the last group of columns to fail, had already failed by the time all 3 of these images were taken. The upper section was actually collectively sliding southward in all 3 of these images.
COMPARISON OF NIST DESCRIPTION OF EARLY MOVEMENT WITH THE ACTUAL VISUAL RECORD
EARLIEST DETECTABLE MOVEMENT
In order to discover the sequence in which columns failed, one could trace early movement of various points on the building back to the point in which movement is undetectable. This was done by independent researchers and the results are displayed in section 2.4 of this book. Interestingly, the NIST didn't detect this earliest movement beginning about 10 seconds before the visible collapse. There is no mention or recognition of the earliest motion detectable in the antenna and the northwest corner within the NIST reports.
This movement from 9.5 seconds before the visual collapse are the earliest sign of collapse initiation, not the 98th floor failure 9.5 seconds later as the NIST claims. Motion can be traced back to determine the earliest moment of detectable motion. The NIST did not do this.
The NIST claims the first signs of collapse initiation were from ejections along the 98th floor. The first visible ejections were actually from the ~87th floor and they were followed by a second set of ejections along the 95th floor.
The ejection emerges about 20 floors below the point that the NIST describes as the failure elevation. It is not mentioned within the NIST reports.
The NIST clearly states, repeatedly, that there was at least an 8 degrees of tilt caused by the failure of the south wall as columns failed from south to north. But all core and perimeter columns had failed before any vertical component tilted 1 degree. Their entire collapse initiation scenario is based on this false assumption; that both WTC1 and WTC2 tilted about the same magnitude during the initial column failure sequence.
The NIST claims that the south wall failed first and redistributed the load to the core and adjacent east and west walls. But points traced on the antenna and the NE, NW and near the SW corner reveal concave deformity along the roofline, not convex deformity or the whole upper portion tilting as a "rigid block" as the NIST claims.
THE SCIENTIFIC METHOD REVIEWED
The final step K in the NIST methodology as stated in the executive summary is to:
"Determine the probable collapse sequence for each tower. A probable collapse sequence for each tower was determined. The collapse sequences were evaluated against key observables."
In the case of WTC1 the key observables concerning the earliest detectable movement, the earliest signs of overpressurization and the movement over the collapse initiation column failure sequence were all misrepresented within the report. If the movement over the collapse sequence is grossly misrepresented within the reports, how can the NIST evaluate their collapse sequence against the behavior of the tower itself?
A quick review: What is the Scientific Method? Wikipedia link here
The most salient points from the link are reviewed:
1) Must be based on gathering observable, empirical and measurable evidence subject to specific principles of reasoning.
Needless to say, the observations and measurements must be accurate.
2) Consists of systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.
In the case of the NIST reports, the collapse initiation sequences are the hypotheses. The hypotheses are tested by comparing them with what was observed and measured. If measurables and observables do not match the hypothesis, one modifies the hypothesis, not the observations and measurements.
Instead, the NIST effectively modified the observables and measurables to match the hypothesis. As explained in part 1, the most fundamental constraint of a physical theory is that it conform itself to all observables and measurables. Careful, accurate observation and measurement are the anchors which limits a model of a physical event to realistic constraints.
3) Scientific researchers propose hypotheses as explanations of phenomena, and design experimental studies to test these hypotheses. These steps must be repeatable, to predict future results.
They need to be verifiable by others so that faith is not required to confirm claims. The NIST has still not released their computer simulations upon which their WTC1 collapse initiation hypothesis rests.
4) Expectation of full disclosure is to document, archive and share all data and methodology so they are available for careful scrutiny by other scientists. This allows statistical measures of the reliability of these data to be established.
Under careful scrutiny by independent researchers, every key observable which the NIST claims occurred during the collapse initiation sequence was found to be verifiably untrue.
The central importance of testing any physical theory by checking how well it matches observables and measurements is once again explained by Richard Feynman:
Within the NIST reports on WTC1, observable, measurable evidence was basically fabricated into a form which superficially appears to agree with the NIST collapse initiation model.
The NIST grossly misrepresented observables during collapse initiation. They grossly misrepresented the movement through the initial column failure sequence. They failed to detect the earliest movement, which was the antenna and the NW corner pulling in, both signs of core failure. The NIST incorrectly identified earliest ejections as from floor 98. In short, every representation of the initial movement of WTC1 within the reports is verifiably incorrect.
Now that these errors are documented, the chance that the NIST will modify their hypothesis of how and why WTC1 collapsed is...virtually nil.
Comparison between the NIST and FEMA descriptions of WTC1 collapse initiation movement and behavior
This is how FEMA described what they considered the failure mode which matched observables in their 2002 study (chapter 2), before the NIST took over the investigation:
"Review of videotape recordings of the collapse taken from various angles indicates that the transmission tower on top of the structure began to move downward and laterally slightly before movement was evident at the exterior wall. This suggests that collapse began with one or more failures in the central core area of the building. This is consistent with the observations of debris patterns from the 91st floor, previously discussed. This is also supported by preliminary evaluation of the load carrying capacity of these columns, discussed in more detail in Section 2.2.2.2. The core columns were not designed to resist wind loads and, therefore, had less reserve capacity than perimeter columns. As some exterior and core columns were damaged by the aircraft impact, the outrigger trusses at the top of the building shifted additional loads to the remaining core columns, further eroding the available factor of safety. This would have been particularly significant in the upper portion of the damaged building. In this region, the original design load for the core columns was less than at lower floors, and the column sections were relatively light. The increased stresses caused by the aircraft impact could easily have brought several of these columns close to their ultimate capacity, so that relatively little additional effects due to fire would have been required to initiate the collapse. Once movement began, the entire portion of the building above the area of impact fell in a unit, pushing a cushion of air below it. As this cushion of air pushed through the impact area, the fires were fed by new oxygen and pushed outward, creating the illusion of a secondary explosion."
So this was the FEMA theory when the NIST took over the investigation in 2002. They saw visual evidence that elements in the central core gave way first.
Until 2010 there was no effort to map the initiation sequence carefully enough to see if the FEMA observations were more correct than those of the NIST.
Now, for the first time, such superior mappings are available and it can be verified by anyone who uses the tools currently available that FEMA described the initiation movements better than the NIST, though with many omissions in their descriptions of the actual observed behavior. Both parties used their own interpretation of the initiation behavior to validate their models.
HOW DID GROSS MISCHARACTERIZATIONS OF WTC1 FAILURE GO UNNOTICED BY SO MANY PROFESSIONAL AND ACADEMIC GROUPS AND INDIVIDUALS SINCE 2005?
This may be one of the biggest mysteries about the reports; how few people seemed to notice the gaping contradiction between the visual record and the NIST's written records of early WTC1 movement.
As of this date there is no written record or any evidence that any independent professional or academic group or individual spotted the gross contradictions between the visual record and the official description and measurements of the initial failure sequence. There is nothing within any engineering study available that seemed to notice the extreme errors in the results.
One reason for this is because engineers and other researchers were never given a visualization of the collapse initiation mechanism from the NIST FEA results. A news article from the magazine New Civil Engineer out of the UK:
WTC investigators resist call for collapse visualisation
1 November, 2005 | By Dave Parker
News
WORLD TRADE Center disaster investigators are refusing to show computer visualisations of the collapse of the Twin Towers despite calls from leading structural and fire engineers, NCEI has learned.
Visualisations of collapse mechanisms are routinely used to validate the type of finite element analysis model used by the investigators.
The collapse mechanism and the role played by the hat truss at the top of the towers has been the focus of debate since the US National Institute of Standards & Technology (NIST) published its findings (see page 10).
NIST showed detailed computer generated visualisations of both the plane impacts and the development of fires within WTC1 and WTC2 at a recent conference at its Gaithersburg HQ. But the actual collapse mechanisms of the towers were not shown as visualisations.
University of Manchester, UK, professor of structural engineering Colin Bailey said there was a lot to be gained from visualising the structural response.
'NIST should really show the visualisations; otherwise the opportunity to correlate them back to the video evidence and identify any errors in the modelling will be lost, ' he said.
University of Sheffield professor Roger Plank added that visualisations of the collapses of the towers 'would be a very powerful tool to promote the design code changes recommended by NIST.' NIST told NCEI that it did not believe there is much value in visualising quasi-static processes such as thermal response and load redistribution up to the point of global collapse initiation and has chosen not to develop such visualisations.
But it said it would 'consider' developing visualisations of its global structural collapse model, although its contract with the finite element analysis subcontractor was now terminated.
A leading US structural engineer said NIST had obviously devoted enormous resources to the development of the impact and fire models.
'By comparison the global structural model is not as sophisticated, ' he said.
'The software used has been pushed to new limits, and there have been a lot of simplifications, extrapolations and judgement calls.
'This doesn't mean NIST has got it wrong in principle, but it does mean it would be hard to produce a definitive visualisation from the analysis so far.'
This same point was repeated numerous times during the 2005 congressional hearing on the results of the NIST report, discussed in detail in section 3.5. It was given as one of five areas of concern of the Skyscraper Safety Campaign. From the hearing:
Finally, the relative secrecy of the investigation and the withholding of all materials and documents used by NIST to arrive at the study's conclusions is very disturbing. These materials should be made available to professionals to further study and to analyze, and to question and verify the findings according to the scientific method. And they should not be locked away in the National Archives or anywhere else.
The actual early movement during the initial column failure sequence as recorded within the visual record was basically replaced by fabricated set of observations and measurements. Early movement as recorded in video reveals movement and failure sequence quite different from anything described within official literature.
There is no accurate technical history of the collapse initiation or collapse progression of WTC1. There is no accurate history or explanation of what happened to WTC1 at all. WTC1 early movement remains a mystery to this day, no official or academic body having measured and mapped its movements or behavior in a remotely accurate way.
In the case of WTC1, a model of collapse initiation was presented that could not at all explain the observables and measurables of early movement. The mistake was not noticed because the NIST reported early movement that was grossly incorrect, and then claimed that the model presented matched all observables.
Most striking is that neither the NIST engineers nor any academic body that supported the final report seemed to notice. Even today, any group or individual can chart early movement of the building, compare with the NIST description of early movement, and notice the gaping difference between the NIST description and reality.
Direct Evidence of a Poor or Non-existent Review Process
WTC1 serves as proof that observables and measurables can be grossly misreported in order to match a conceptual model with very few people noticing. One decade after the collapses, and over 5 years after the final NIST reports were published, one has an excellent opportunity to look back at how the misreported early movement of WTC1`was received by the general public.
The multiple indications of collective core failure would have been recognized from a careful study of the visual record and early building movement. Yet, it still goes unrecognized today.
