NATURAL HISTORY. 89 



reason, have more heat than great ones ; because the 

 action of the heart and arteries increases in proportion 

 to the comparative smallness of the animal. Till the 

 aga of three years the life of infants is extremely pre- 

 carious ; in the course of the ensuing second or third 

 years it becomes mere certain, and at six or seven a 

 child has greater probability of living than at any 

 other period of life. It is remarked, that of a certain 

 number of children born at the same time, above a 

 fourth die in the first year ; above a third in twa 

 years, and at least one half in three years. By other 

 calculations, it appears that one half of the children 

 born at the same time are not extinct in less than se- 

 ven or eight years. 



At twelve or fifteen months infants begin to lisp* 

 A is the vowel which they pronounce with most ease. 

 Of the consorlants, B, M, P, T, are most easy. In 

 every language, therefore, Baba, Mama, Papa, are 

 the first words that children learn. Some children 

 pronounce distinctly in two years, though the gene- 

 rality do not speak for two years and a half. 



Some young persons cease growing at fourteen or 

 fifteen, while others continue their growth to twenty- 

 two or twenty-three. In men the body attains, its 

 perfect proportion at the age of thirty, and in women 

 sooner. The persons indeed of women are generally 

 complete at twenty. The distance between the eyes 

 is less in man than in any other animal ; in some 

 creatures, in fact, the eyes are at so great a distance, 

 that it is impossible they should ever view the same 

 object with both eyes at once. Men and apes are the- 

 only animals that have eye-lashes on the lower eye- 

 lid. Other animals have them only on the upper one. 



Vol. I. L 



