This is 17th century astrologer William Lilly's advice on how to judge the welfare of several persons missing. Paraphrased from Christian Astrology, pages 430-431 of Christian Astrology.
It sometimes happens that 4 or 5 people are travelling together in a distant land and the querent wishes to hear news of each of them. In this case, ask the querent to write down all their names in order.
The first person named on the list is shown by the Moon's first application. Look to the condition of that planet - where it is positioned, how it is dignified, by whom it is aspected, from where it is separating and to where it is applying -and judge the state, condition, health and welfare of the first person named accordingly.
Do the same using the planet to whom the Moon applies next for the second man named on the list, and so on for the rest of the names.
If there are more names than there are planets, go around them all more than once, remembering to take note of whether the planet is retrograde, direct, combust, etc..