Plate CCXCH showing various surveying levels and their components, labeled Fig. 1 through Fig. 14.

This plate illustrates various surveying levels and their components, labeled Fig. 1 through Fig. 14:

  • Fig. 1: A long, thin level with a central support and adjustment screws.
  • Fig. 2: A long, thin level with a central support and adjustment screws.
  • Fig. 3: A spirit level with a vertical column and a circular base.
  • Fig. 4: A tall, thin level with a circular base and adjustment screws.
  • Fig. 5: A tall, thin level with a circular base and adjustment screws.
  • Fig. 6: A spirit level with a vertical column and a circular base.
  • Fig. 7: A small, triangular level with a circular base.
  • Fig. 8: Two small, thin levels with circular bases.
  • Fig. 9: A large, thin level with a circular base and adjustment screws.
  • Fig. 10: A small, thin level with a circular base.
  • Fig. 11: A small, thin level with a circular base.
  • Fig. 12: A small, thin level with a circular base.
  • Fig. 13: A large, thin level with a circular base and adjustment screws.
  • Fig. 14: A tall, thin level with a circular base and adjustment screws.
A blank, aged page with a light beige background, showing significant water damage and staining. The page is framed by a faint, light brown border. There are several large, irregular brown stains, particularly a prominent one in the lower right quadrant and another near the bottom center. The overall texture appears slightly grainy and aged.This image shows a blank, aged page with a light beige background. The paper has a slightly grainy texture and shows signs of significant water damage and staining. A faint, light brown border is visible around the edges of the page. There are several large, irregular brown stains, most notably a prominent one in the lower right quadrant and another near the bottom center. The overall appearance is that of an old, weathered document page.

Fig. 1.

Fig. 1: A detailed cross-sectional diagram of a leveling instrument. It shows a long horizontal bar with various components labeled. At the top is a thick dark bar. Below it is a thinner bar with a central section labeled 'X'. Two large rectangular blocks labeled 'L' are positioned on either side of the central section. The entire assembly is supported by a base with several vertical supports labeled 'H' and 'I'. The outer edges are labeled 'A' and 'B' on the left, and 'C' and 'D' on the right.

Fig. 2.

Fig. 2: A diagram showing a leveling instrument with multiple horizontal bars. Two large rectangular blocks labeled 'L' are at the top and bottom. Between them are three horizontal bars. The middle bar has a central section labeled 'P' and a threaded section on the right. The outer bars have various labels including 'O', 'V', 'M', 'Q', 'T', 'S', and 'N'.

Fig. 3.

Fig. 3: A diagram of a leveling instrument showing a long horizontal bar with a central section labeled 'P'. The ends are labeled 'A'. Below the bar, the labels 'H' and 'X' are visible.

Fig. 4.

Fig. 4: A diagram showing two small leveling instruments, each labeled 'D', positioned on a base. A curved line connects the two instruments, representing a leveling line.

Fig. 5.

Fig. 5: A diagram of a leveling instrument showing a long horizontal bar with a central section labeled 'P'. The ends are labeled 'D'. Below the bar, the label 'G' is visible.
Faint architectural drawing of a building facade with a central dome and multiple horizontal levels.A faint architectural drawing of a building facade, possibly a church or cathedral. The drawing shows a central dome on top of a rectangular structure. Below the dome, there are several horizontal levels or tiers, each with different architectural details. The drawing is very light and appears to be a watermark or a faded print. The entire page is covered with numerous brownish stains, likely from water damage or age.
Fig. 1.
Geometric diagram Fig. 1 showing a vertical line MM' and a horizontal line NB intersecting at point N. A dashed line m-n passes through N, representing a line of sight.

Fig. 1 is a geometric diagram showing a vertical line MM' and a horizontal line NB intersecting at point N. A dashed line m-n passes through N, representing a line of sight.

Fig. 2.
Perspective drawing of a leveling instrument (Fig. 2) consisting of a horizontal tube AB mounted on a cylindrical base. The base has a small rectangular window with a viewing vane. The instrument is placed on a flat surface CD.

Fig. 2 is a perspective drawing of a leveling instrument. It consists of a horizontal tube AB mounted on a cylindrical base. The base has a small rectangular window with a viewing vane. The instrument is placed on a flat surface CD.

Fig. 3.
Geometric diagram Fig. 3 showing a large inverted triangle with vertex T. A horizontal line AC is drawn through the triangle. A vertical line passes through O and D. A curved line segment connects points on the triangle. A dashed line represents a line of sight.

Fig. 3 is a geometric diagram showing a large inverted triangle with vertex T. A horizontal line AC is drawn through the triangle. A vertical line passes through O and D. A curved line segment connects points on the triangle. A dashed line represents a line of sight.

Fig. 4.
Geometric diagram Fig. 4 showing a right-angled triangle ABC with the right angle at B. A curve is drawn from point C to point A, passing through point D.

Fig. 4 is a geometric diagram showing a right-angled triangle ABC with the right angle at B. A curve is drawn from point C to point A, passing through point D.

A blank, aged page with a light beige background, showing significant water damage and staining, particularly along the left edge and bottom. The page has a faint, large, light blue watermark or impression in the center, resembling a stylized floral or geometric pattern. The overall texture is slightly grainy, and there are numerous small brown spots (foxing) scattered across the surface.This image shows a single, blank page of aged paper. The paper has a warm, light beige or cream-colored tone. There is a prominent, large, faint watermark or impression in the center of the page, which appears to be a stylized floral or geometric pattern, possibly a sunburst or a complex star shape. The paper is heavily stained, particularly along the left edge and the bottom, with large, irregular brown and tan patches that suggest water damage or age-related discoloration. Numerous small, dark brown spots, known as foxing, are scattered across the entire surface. The overall texture of the paper looks slightly grainy and uneven.

Fig. 4.

A detailed topographical map showing a survey area with a river, fields, and wooded areas. A large irregular polygon is outlined in the center. A smaller rectangular inset in the bottom right corner shows a cross-section of terrain with vertical markers labeled A, B, C, D, E, F, G, H, I, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z, and a horizontal line labeled 'Fig. 1.' and 'Fig. 2.'

Fig. 5.

A topographical map showing a survey area with a river, fields, and wooded areas. A large irregular polygon is outlined in the center. A smaller rectangular inset in the bottom right corner shows a cross-section of terrain with vertical markers labeled A, B, C, D, E, F, G, H, I, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z, and a horizontal line labeled 'Fig. 6.'

PROFILE

Fig. 7.

A profile view of a landscape showing a series of hills and a building on the left. The profile is marked with vertical lines and labels A, B, C, D, E, F, G, H, I, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z, and a horizontal line labeled 'Fig. 8.'
A large, faint, sepia-toned portrait of a man, likely a historical figure, centered on the page. The portrait is rendered in a soft, sketch-like style with visible brushstrokes and shading. The man has a high forehead, receding hair, and is wearing a dark, formal suit with a white shirt and a dark cravat or necktie. The background of the portrait is light and textured, suggesting a studio backdrop. The overall image is aged and has a warm, sepia tone.

CHARLES
DARWIN