210 A Tribute to the Memory of 
which continued, without interruption, until 
it was terminated by the death of Dr. Perci- 
val, in 1804. It was about the same early pe- 
riod, that he formed an acquaintance with that 
excellent man, and upright magistrate, the 
late Mr. Bayley of Hope-Hall, and much of 
the happiness of his future life was owing to 
the mutual esteem and confidence, and to the 
frequent intercourse, which continued to ex- 
ist between them for more than thirty years.* 
During his apprenticeship, Mr. Henry had 
manifested a decided taste for chemical pur- 
suits, and had availed himself of all the means 
in his power, limited as indeed they were, to 
become experimentally acquainted with that 
science. ‘This taste he continued to indulge 
after his settlement in life; and, after having 
made himself sufficiently master of what was 
ascertained in that department of knowledge, 
he felt an ambition to extend its boundaries. 
In the year 1771, he communicated, to the 
Royal College of Physicians of London, “‘ An 
Improved Method of Preparing Magnesia 
Alba,” which was published in the second vo- 
lume of their Transactions. 'Two years af- 
* An interesting biographical sketch of Mr. Bayley, 
written by Dr. Percival, appeared in one of the volumes 
of the Monthly Magazine for the year 1802. 
