// Blindness ....is rare ( I suppose because very few people do it and clinical trial have difficulty in getting volunteers// Sqad
because we dont do it !
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1991080/
Retinal Burns After Sun's Eclipse. M. J. Gilkes,
The Gilkes here is also the one who described retinal haemorrhages in shaken babies (Lancet 1962) - and from whom I bought er thro Christies, his first edition Gray's Anatomy. He is also descended from a doctor-VC during the Great War - but not Chavasse.
[oh well this comment makes a difference from the usual AB fare of "why dont we get Brexiters/terroristen/scum and hold their eyes open and make them look at the sun and blind them?" and this will mean they cant vote again/shoot people/something else]