DOI Page / Citation link:
https://doi.org/10.11588/diglit.4423#0090
THE APPARENT PROPORTIONS,
63
By these forms of calculation the amounts of the corrections are determined trigono-
metrically for No. 1 and No. 2 Designs, and a comparison with Plate III., Part I., shows how
closely the corrections ascertained hy calculation agree with those derived from observation.
The Amount of the Corrections Ascertained by Calculation.
Column.
No. 1 Design.....+ 5"6 in.
No. 2 Design . . . ■ . . + 5*5 „
Corrections derived from ooserration )
+ 5-55,,
(see Plate III., Part I.) . . )
Entablature.
Pediment.
Steps.
Whole Height.
— 1-8 in. .
. — 7-8 in. .
+ 6'6 in.
. + 10-5 in.
— 12 „ .
• — 8-2 „ .
• + 0-6 „
— T25„
— 8-1
+ 0-6 „
Comparing together the two designs of the Parthenon, it will be seen that the amounts
of the corrections, namely, the small plus and minus quantities, are the same for both designs,
although the visual angles and the points of view are found to vary in the two examples.
In the south-east angular view, No. 2, the arrangement of the design of the Stylobate
differs from the north-west angular view, No. 1, thus—
The length of the diagonal line.....
The distance from the Architrave to the point of sight 0
The point of sight, 0, below the Upper Step
No. 2 Design.
277-906 ft.
166-117 „
9-2
»
No. 1 Design.
262-79 ft.
159-11 „
19-2 „
The result of these changes in the first given quantities is that the calculated variations
become the same for the two designs, and that all the executed dimensions are similar. It was,
therefore, sufficient in the Parthenon to calculate and correct one design only, and then, by
adjusting the point of sight and the length of the diagonal line, the calculated vertical dimen-
sions in the two designs became the same.
We might at once proceed to the consideration of the horizontal curves of the Parthenon,
but, as each step in the ancient theory of design requires to be established by ample proofs, I
have preferred to lay down in the same way the first lines of the two designs of the Erechtheium,
and of the two designs of the Propylsea, to show how the same principles were applied equally
to all designs, large and small.
It is only in designs of magnitude, like the Parthenon, the Propylsea, and the
Erechtheium, and when the points of view were clearly defined, that these corrections were
made; but in designs, such as these were, the Greek principle of designing perspectively, and
of making all the visual angles commensurable, was, I believe, correct in theory.
63
By these forms of calculation the amounts of the corrections are determined trigono-
metrically for No. 1 and No. 2 Designs, and a comparison with Plate III., Part I., shows how
closely the corrections ascertained hy calculation agree with those derived from observation.
The Amount of the Corrections Ascertained by Calculation.
Column.
No. 1 Design.....+ 5"6 in.
No. 2 Design . . . ■ . . + 5*5 „
Corrections derived from ooserration )
+ 5-55,,
(see Plate III., Part I.) . . )
Entablature.
Pediment.
Steps.
Whole Height.
— 1-8 in. .
. — 7-8 in. .
+ 6'6 in.
. + 10-5 in.
— 12 „ .
• — 8-2 „ .
• + 0-6 „
— T25„
— 8-1
+ 0-6 „
Comparing together the two designs of the Parthenon, it will be seen that the amounts
of the corrections, namely, the small plus and minus quantities, are the same for both designs,
although the visual angles and the points of view are found to vary in the two examples.
In the south-east angular view, No. 2, the arrangement of the design of the Stylobate
differs from the north-west angular view, No. 1, thus—
The length of the diagonal line.....
The distance from the Architrave to the point of sight 0
The point of sight, 0, below the Upper Step
No. 2 Design.
277-906 ft.
166-117 „
9-2
»
No. 1 Design.
262-79 ft.
159-11 „
19-2 „
The result of these changes in the first given quantities is that the calculated variations
become the same for the two designs, and that all the executed dimensions are similar. It was,
therefore, sufficient in the Parthenon to calculate and correct one design only, and then, by
adjusting the point of sight and the length of the diagonal line, the calculated vertical dimen-
sions in the two designs became the same.
We might at once proceed to the consideration of the horizontal curves of the Parthenon,
but, as each step in the ancient theory of design requires to be established by ample proofs, I
have preferred to lay down in the same way the first lines of the two designs of the Erechtheium,
and of the two designs of the Propylsea, to show how the same principles were applied equally
to all designs, large and small.
It is only in designs of magnitude, like the Parthenon, the Propylsea, and the
Erechtheium, and when the points of view were clearly defined, that these corrections were
made; but in designs, such as these were, the Greek principle of designing perspectively, and
of making all the visual angles commensurable, was, I believe, correct in theory.