PREFACE. XVI I 



excellent method of strengthening their habits of 

 observation, attention, and memory, equal per- 

 haps, in this respect, to any other mental exercise: 

 and then, like Major Gyllenhal, who studied En- 

 tomology under Thiinberg about 1770, and after 

 an interval of twenty years devoted to the service 

 of his country, resumed his favourite pursuit with 

 all the ardour of youth, and is at this time giving 

 to the world a description of the insects of Sweden 

 invaluable for its accuracy and completeness — 

 they w ould be provided in their old age with an 

 object capable not merely of keeping off that 

 tcediiim viltE so often inseparable from the relin- 

 quishment of active life, but of supplying an un- 

 failing fund of innocent amusement, an incentive 

 to exercise, and consequently no mean degree of 

 health and enjoyment. 



Some, who, with an ingenious author*, regard 

 as superfluous all pains to show the utility of Na- 

 tural History in reference to the common pur- 

 poses of life, asking " if it be not enough to open 

 a source of copious and cheap amusement, which 

 tends to harmonize the mind, and elevate it to 

 worthy conceptions of nature and its Author ? 

 if a greater blessing to a man can be offered than 

 happiness at an easy rate unalloyed by any de- 



* Dr. Aikin. 

 VOL. I. b 



