162 A EULOGY OF RAY, DALE AND ALLEN.
As his pupil Dale was recommended to Ray by their common
love of botany ; so, since, as we have seen, from about 1690,
Willughby's unfinished work had directed Ray's attention very
largely to insects, it was his studies in entomology that recom-
mended Allen to his illustrious neighbour at Black Notley.
In 1692 Allen observed that some glow-worms had wings and
also discovered a Death-watch Beetle. The latter he showed
to Ray, "while it was yet alive and did beat" ; while from the
former observation Ray correctly inferred that the winged glow-
worms were male and the wingless ones female.
A little later Allen communicated to the Royal Society,
possibly through Ray, the only papers of his that were published
in the Philosophical Transactions. These were one "On
the Manner of Generation of Eals" (1698), which elicited some
friendly criticism from Dale ; one on the Death-Watch (1699),
illustrated by figures drawn with the help of a microscope ; and
one on the bee observed in Aleppo Galls.
The friendship with Ray between 1692 and 1697 was destined
to be interrupted. One of Ray's twin daughters, apparently
an anaemic child, died while under treatment by Allen, although
he alleges that a preparation of steel prescribed by him was
not used ; and the father thinking there had been want of
care or of skill, a coolness arose between them. This breach
was, however, healed before Ray's death ; or, at least, it did
not prevent Allen writing of Ray in his book on Chalybeate
Waters, published in 1699, as his "honoured friend," or Ray
writing of Allen in his History of Insects in similar terms. Ray
seems never, however, to have been in the same degree intimate
with Allen as with Dale.
In publishing his Natural History of the Chalybeat and Purging
Waters of England in 1699, Allen excuses "the impertinences
and imperfections of it" on the ground that it was, as we have
said, largely written while he was an undergraduate—written
hurriedly and never read over until printed ; but, judging
by the note-books drawn up by him in mature years, we cannot
avoid admitting that Allen, though a careful and accurate
observer and a not unskilful draughtsman, is singularly deficient
in the power of writing clear English. The book itself is in-
teresting as the first systematic treatment of our English medicinal
waters, and to us in Essex, more especially, as describing eight