188 



Experiments for ascertaining the Velocity of Sound, at Madras in the 

 East Indies. By John Goldingham, Esq. F.R.S. Read February 

 20,1823. [Phil. Trans. 1823, p. 96.] 



The author commences this paper with an abstract of the opinions, 

 experiments, and calculations of several eminent philosophers who 

 have studied the above subject ; and after remarking upon their dis- 

 cordant results, observes that his own experiments may perhaps fur- 

 nish a clue for discovering the cause of such differences. These were 

 made at Fort St. George, where a morning and evening gun are 

 fired from the ramparts, the former at daylight, and the latter at 8 

 o'clock in the evening. Morning and evening guns are also fired at 

 St. Thomas's Mount ; and between these the Madras Observatory is 

 situated, in latitude 13 4' 8" N., at which the observations were made 

 with chronometers of 100 beats in 40 seconds. Each observer began 

 to count the beats in the interval of the flash and report. Their 

 number was registered, as well as the height of the thermometer, 

 barometer, and hygrometer, and the state of the wind and weather 

 at the time. The distances of the guns from the observatory were 

 ascertained with much precision ; that of the Mount gun being 

 29547 feet, and of the Fort gun 13932-3 feet. The results of these 

 experiments are given in eleven annexed tables. From Tables 1 and 

 6, it appears that the velocity of sound is much affected by different 

 states of the atmosphere and weather ; and from Tables 2 and 7, we 

 find as the thermometer rose, the atmosphere at the same time de- 

 creasing in density, sound moved with increased rapidity. The mean 

 velocity of sound deduced from these experiments appears to be 

 1142 feet in a second, which closely corresponds with the estimate 

 of Newton and Halley. The comparison of the experiments with the 

 Mount and Fort guns seems to show that sound travels equally in its 

 progress ; and by comparing the observations upon the influence of 

 wind, a difference is found of 1275 feet in a minute between the 

 wind being in the direction of the motion of the sound, and opposed 

 to it. 



On the Double Organs of Generation of the Lamprey, the Conger Eel, 

 the common Eel, the Barnacle, and Earth Worm, which impregnate 

 themselves ; though the last from copulating, appear mutually to im- 

 pregnate one another. By Sir Everard Home, Bart. V.P.R.S* 

 Read February 27, 1823. [Phil. Trans. 1823, p. 140.] 



Having previously ascertained the teredo and the lamprey to be 

 hermaphrodites, and that in these tribes the same individual both 

 forms and impregnates the ova, the author shows upon the present 

 occasion, that eels and barnacles are similar in their mode of gene- 

 ration. In respect to the former, the author adopts the opinion of 

 Sir Humphry Davy, that the common and the conger eel belong to 

 the same species, their difference in size and colour depending upon 

 the one living in fresh and the other in salt water. Their organs of 



