Summary

CD’s questions [on expression] are more difficult than he thought and have led him further afield than he expected. If CD is not hurried, he promises less imperfect answers in six weeks. Thanks CD for drawing his attention to a really important question from different points of view.

Summary

The illness and death of his daughter have delayed his answers to CD’s queries. He has, however, worked on the circulation of the eye and has almost finished a paper on it, which he will send to CD. In general, the views of Charles Bell are confirmed.

As for CD’s second query, he doubts that the relationship exists, but will answer fully in next letter.

Summary

Has finished the article [on the action of the eyelids in Ned. Arch. Geneeskd. & Natuurkd. 5 (1870), also see 7238]; summarises: the occlusion of the eyelids protects the vessels, and the eye itself, against the danger of pressure caused by excessive expiratory action. The weakness of the conclusion is that the extent of the danger caused by the pressure to the normal state of the eye is not precisely known.

Summary

A detailed description of the physiological and anatomical processes related to the prolonged involuntary contraction of the orbicular muscles and the secretion of tears (as in retching, violent coughing, or laughing). [See Expression, p. 160.].

Summary

Thanks CD for Descent.

Sends a copy of his oratio inauguralis on De harmonie van het dierlijke leven [1848] in which he espoused evolution, but did not see the influence of natural selection.

Summary

Answers to CD’s queries will take time. CD may not be aware of the influence of accommodation on the diameter of the pupil of the eye. Parrots, for example, contract or dilate the pupil independently of amount of light [see Expression, p. 304]. Sends his book on the subject [On the anomalies of accommodation and refraction of the eye (1864)].

Summary

Replies to CD’s queries on movement of the eyes in meditation, and changes in the iris in rage and terror [see Expression, pp. 229, 304].

Summary

His analysis and explanation of the fact, observed by Charles Bell, that the eyeballs are turned upwards and inwards when consciousness begins to fail.

Summary

Protests against CD’s statement that FCD’s letter will make him "strike out a good deal". He would never pardon himself for being the cause of any suppression by CD. It is for specialists to put their knowledge at CD’s service. He is mistaken if he thinks a knowledge of physiology is sufficient for writing a book on expression. It is CD’s conception and spirit that all await. Offers to read those parts of the proofs of Expression dealing with physiology.

Summary

Royal Netherlands Academy of Science has elected CD.

Summary

Thanks CD for invitation but declines because of his need for a rest instead of coming to England in July.

Repeats his offer to help CD at any time. "I am always learning by trying to answer your questions."

Summary

Thanks CD for copy of Expression.

Agrees to observe expression in children born blind.

Summary

On hearing of CD’s work with Drosera, tells of his experiment showing extreme sensitivity of the iris of a dog’s eye to atropine. [See Insectivorous plants, p. 173.]