Ordered Pairs

About the Artist and Artwork

Bartolommeo, Fra (Italian, 1472-1517)

Baccio della Porta, who was later known as Fra Bartolommeo after he took religious orders, was apprenticed to the painter Cosimo Rosselli at the age of thirteen. This placed him at the center of a community of Florentine artists during his training. His ability to incorporate what he learned allowed him to develop an appealing style that later brought him major commissions, including the Vision of Saint Bernard for the cathedral of Lucca. A frequent collaborator of Mariotto Albertinelli, who had also trained with Rosselli, Fra Bartolommeo received his most important commission in 1510, an altarpiece for the Sala Grande (now the Salone dei Cinquecento) in the Palazzo della Signoria in Florence. The unfinished altarpiece is now in the Museo di San Marco.

Fra Bartolommeo popularized the use of black chalk, bringing a new facility and texture to the medium. In this drawing, the contrast between smooth skin, filmy drapery, and feathery wings is brought out by touches of white chalk. The figure, a music-making angel meant for the steps below an enthroned Madonna, shows the artist’s experimentation with different angles of the head.

Lesson Procedure

Day 1

1. Have students look carefully at the image, Seated Angel Playing a Lute. This image is accessible on Digital Crocker at crockerartmuseum.org, on the Striking Gold CD ROM, and slides and overheads available for purchase through School Services.

2. Summarize Seated Angel Playing a Lute to the students and provide a definition of “friar,” “sacra conversazione,” and altarpiece.

3. Lead an open class discussion with questions, and record all comments on the board. Ask:

   a. What image do you see? Why do you think it looks like the angel has two faces?

     b. What shapes do you see? Where do you see vertical lines? Where do you see horizontal lines? Where do you see diagonal lines?

     c. How does the artist show volume? How does the artist show the texture of skin? How does the artist show the texture of fabric? How does the artist show the texture of feathers? Compare (similarities and differences) this representation with objects found in nature.

     d. Why do you think the artist has drawn the image over a grid? (The artist intended this for a larger piece or to transfer it to the final version.) How many lines do you count vertically? How many lines do you count horizontally? Where is the center of the grid?

     e. What other things remind you of a grid? Have you looked at a road map? How would you tell your friends how to find your house? How many of you have been to the State Fair? How would you use a map of the fairgrounds to find the ponies and horses? How do you find your car in the expansive parking lot at the end of the day?

4. Have students draw a dark line on the handout across the center vertical and horizontal lines on the handout of Seated Angel, label them x and y, and write in the corresponding numbers for each axis. Break students into groups and have them discuss the following math problems:

     a. Where is the location of the angel’s big toe on her left foot? What is the ordered pair for that point on the graph?

     b. Where is the location of the angel’s right hand that is strumming the lute? What is the ordered pair for that point on the graph?

     c. What is found at (0, 3)?

     d. Draw a dark line that represents the equation x = - 4.   What part of the image is located on that line?

Day 2

1. Art production: Distribute the handout of the horse drawing (see example in “Downloads”). Have students draw an x axis under the horse’s belly and a y axis behind the horse’s front left leg directly on the handout.

2. Distribute 8 ½” x 11” white paper and have students draw the x and y axes lines so that they intersect in the center of the paper, which is positioned horizontally (landscape). If students have difficulty drawing the axes straight by sight, show them how to measure the lines from the paper’s edges.

3. Write a point on the y axis that measures 2 ½” above the x axis and label it (0, 2 ½). Very lightly draw a horizontal line across that point and label the line “back.” Write a point on the y axis that measures 2 ½” below the x axis and label it (0, -2 ½). Very lightly draw a horizontal line across that point and label the line “grass.”

4.   Write a point on the x axis that measures 3” to the right of the y axis and label it (3,0). Very lightly draw a vertical line through the point and label the line “tail.” Write a point on the x axis that measures 3” to the left of the y axis and label it (-3, 0). Very lightly draw a vertical line through the point and label the line “neck.”

5. Have students write a mark in one-inch increments on the x and y axes and label them 1, 2, 3, -1, -2, -3 as appropriate.

6.   Draw the horse step by step on a white board while the students follow. First draw a light line for the horse’s back that is shaped like two low hills. Ask the students to identify the ordered pairs closest to where this line begins and ends ((-2,2) and (3,2)).

7. Draw a curved line from (-2, 2) and curving slightly to the right of (-3, -2 ½). This line is the top of the horse’s neck and head. Remind the students to glance often at the drawing handout. They should observe the angles and curves of the lines on the handout for accuracy.

8. Draw a line from (0, 0) to (1/2, -2 ½) and draw a parallel line to the left of it for the horse’s leg (should be about ¼” thick). Draw a diagonal line from (-1, -1/2) to (-1 ½, -2 ½) and draw a parallel line to the left for the other front leg. Connect the two front legs with a rounded triangular line at the top.

9. Draw the negative space between the neck, head, and front leg like a stretched out foot print from (0, -2) to (-2 ½, -2 ½)

10. Draw a line from the rear of the horse (3, 2) to the grass line, slightly to the left of (3, -2 ½). Adjust the line for realism by curving the line out for the horse’s rear and curving the line in for the horse’s thigh. Draw a parallel line to the left of it to crate the width of the leg. Curve the line so that the thigh is wider and ends slightly above the x axis.

11. Draw a curved line at the x axis that connects the front left leg with the back left leg from (0, 0) to just above (2,0). This is the belly of the horse.

12. Draw the right rear leg as a parallel curved line next to the left rear leg (see handout).

13. Draw hooves at the grass line so that they are slightly rounded. Refine the legs by adding a little curve for the horse’s knees (point out to students that the rear leg has a joint that sticks out). Refine the front left thigh by extending the curved line to show that the leg overlaps the other leg. Remind students that the Italian Renaissance artists were inventing realistic space through perspective.

14. Refine the neck and head (see handout). Add a little open triangle for the mouth and an oval for the nostril. Draw the ear as a curved triangle. Add the eye as an oval with a curved line across the middle for the eyelid.

15. Lightly sketch in the mane and the tail.

16. Lightly sketch in grass using free form organic lines, not straight lines.

Day 3

17. The last step is to shade the horse to show volume and shadow. Point out to students that the light source is coming from above the horse, so the areas on the top of his back and his neck are “highlights” without shading. The areas underneath his neck and on part of his legs are darkest. Areas on the horse’s face and belly are shaded a medium value.

18. End the assignment by having each student select a point on his or her drawing and write a verbal description of that point and its corresponding ordered pair on the back of the drawing.