1 62 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, theonly 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 
