From W. E. Darwin [22? April 1868]1
My Dear Father,
I shall see Langstaff in a day or so, & will ask him to watch as to wing of nose.2
He has seen your first letter & will be very glad to give you any help he can. He will observe as to oblique eyebrow.3 As we had not Bell to refer to, he was anxious to define the action as follows, to be sure that you agreed with him as to the action.4 the orbiculares become rigid, the pyramidalis nasi, and Corrug: supercil: then draw the eyebrows inwards, the centre fibres of the Occipito frontalis then wrinkle the centre part of forehead; the Corrugators are attached at an angle from point of nose, and on contracting they prevent the contraction & counteract the rigidity of inner portion of orbicularis, and allow it to be wrinkled and raised by the occipito frontalis, while the outer portion still remains rigid. The appearance of raising the inner portion of Eye brow is also produced by the arching of corrugator on contraction.
Langstaff seems uncertain also about the gorging of conjunctiva, tears, & contraction of orbicularis: he says you see persons crying without any contraction of orbicularis, but on the other hand in case of ectropion where the pressure of under lid is removed, the lower part of the conjunctiva is always gorged, and the gland is continually secreting.
He is inclined to think that the primary object of contraction is to protect eye from blood, the secondary is not to assist in secreting but to assist in expelling the water from gland, & that the contraction of tensor tarsi will also act for this purpose by drawing the eyelid forwards and inwards & so pressing the eye ball against the gland.
I was on the pier a day or so ago, and a girl of about 15 or 16 lost her hat into the water, and began crying, and restraining herself on my keeping my eye on her; to my great surprise she seemed to me to be trying to cry with her Great Zygomatic
[two pages missing] that it is the contraction of the inner or centre fibres of the occipito frontalis that resist the action of the orbiculares in the case of a seeing on the steam boat a boy was standing with his face towards the sun, and was trying to hear what his father was saying to him thro’ the wind, & naturally as he could not quite hear he was more anxious to look at him notwithstanding the sun, which caused a fine struggle between the two sets of muscles he had a cap rather low down so that I could not well see the transverse wrinkles.
Our affair is still going and I have tolerable hopes of its coming to a head.5
Your affect son | W. E. D.
Langstaff examined a woman lately, who blushed most intensely on the face, but not the least on the thighs.6
C. L. Langstaff on action of muscles in crying. He believes the primary object of the contraction of the orbicularis is to protect the eye from blood.
Blushing on the body.
Please cite as
Darwin Correspondence Project, “Letter no. 6137,” accessed on 10 December 2016, http://www.darwinproject.ac.uk/DCP-LETT-6137