[68] A binocular slide, copied from the one originally designed by myself, forms No. 27 of the Series of white-lined diagrams upon a black ground executed in Paris. The drawings, however, are too large for the common stereoscope.

[69] [See Chap. i. p. 15].

[70] Phil. Trans. 1744.

[71] Letter v. pp. 98-107. See also the Edinburgh Journal of Science, Jan. 1826, vol. iv. p. 99.

[72] Journal, 1839, p, 189.

[73] See Edinburgh Philosophical Journal, November 1832, vol. i. p. 334.

Transcriber’s Notes:

Antiquated spellings were not corrected.

The illustrations have been moved so that they do not break up paragraphs and so that they are next to the text they illustrate.