Luther at once answered in his Asterisks.
Asterisks are placed against those works which have been translated into English.
It represents in the main the text of the later Greek MSS., but it has important textual notes, and has adopted a system of asterisks and obeli from the Hexaplar LXX.
The Aµ from C to F being taken as unity in each case then the AA's for the other regions of the spectrum are expressed in fractions A A (C to F) and are given under the asterisks.
Let it be supposed that two positive lenses of equal curvature powers are made out of these two glasses, then in order to represent the combined dispersion of the two together the two 0µ's for each spectral region may be added together to form 0'µ as in the line below, and then, on again expressing the partial z'µ in terms of L'µ (C to F) we get the new figures in the bottom row beneath the asterisks.
