by Vertical Fire. 295 



tumbling over and over in oblique, irregular directions, with- 

 out any certainty, excepting that the velocity and effect will be 

 much less than those of a round shot of equal weight*." 



Art. XIII. An Account of the good Effects of the white 

 Oxide of Bismuth in' a very severe Stomach Affection of a 

 Gentleman far advanced in Years. By G. D. Yeats, 

 M.D., F.R.S., Fellow of the Royal College of Physi- 

 cians, &c., (communicated by the Author.) 



Many years have now elapsed since Dr. Marcet published a 

 very clear and explicit account of the good effects of the white 

 oxide of bismuth in certain painful conditions of the stomach. 

 Relying upon the recommendation of this medicine, as coming 

 from so respectable an authority, other practitioners very soon 

 made trial of it, and were much gratified in finding that it an- 

 swered the expectations of the curative powers which had 

 been attributed to it. Among those who have since more parti- 

 cularly called the attention of physicians to this subject, is 

 Dr. Bardsley, of Manchester, who, in 1807, published some 

 interesting and instructive cases in his Medical Reports. Some 

 insulated cases have also been published in the medical jour- 

 nals, confirming the high character given to the medical virtues 

 of the oxide of this metal. In reviewing the cases which have 

 been presented to the public, I do not find the age of any one 



* As a practical exhibition of the doctrine of terminal velocity, Sir 

 Howard notices the descent in the parachute, of which the aeronaut, de- 

 taching himself from his balloon, falls with accelerated speed until the 

 resistance of the air to the expanded canopy becomes equal to the total 

 weight of the descending body, after which it falls to the earth with uni> 

 form velocity nearly. To the man of science these illustrations may ap- 

 pear superfluous, and perhaps obtrusive ; but the author knows from 

 experience, that such familiar illustrations are necessary to convey his 

 meaning to those who, like the theorists of no remote period, make no 

 allowance for the resistance nf the air, which is now known to be such 

 that a 24 lb. ball, moving with a velocity of 2,000 feet in a second, would 

 suffer a resistance of 800 lb. nearly. 



