Baeometkic Anomaly. 



241 



not rely on the calculation. The true height is not far 

 from one hundred and twenty-five feet, or one fifth the el- 

 evation of the middle point in the ISTorth American conti- 

 nent.* Taking on board salt fish, turtle-oil, and tiles, we 



* For a discussion of the barometric perturbations on tlie Amazon, see 

 American Journal of Science for Sept., 18G8. 



