47 
experiments made with an invariable pendulum, 
mean number of vibrations in 24 hours is 86223,659 by the 
observation of disappearance, and 86223,800 by the mean 
of disappearance and re-appearance. 
The mean height of the barometer was 29,844 inches, and 
the mean temp.- 50°.i5 ; whence it appears that the specific 
gravity of the pendulum was to that of air, as 7000,6 to 1 , 
which gives 6 T .i58 as a correction additive for the buoyancy 
of the atmosphere. The ball of the pendulum was found by 
levelling to be 121,04 feet above low water ( neap tides ), the 
correction for which by the duplicate ratio of distances from 
the earth's centre (3950,858 miles) is, o T .5oo in 24 hours. 
And as the station was the tabular surface of a bed of secon- 
dary limestone, I suppose the proper multiplier is which 
will give o T .330 for the correction to be added due to this 
elevation. These corrections being applied to the number of 
vibrations before found, will give the number of vibrations 
that would have been made by the pendulum in a mean solar 
day, in vacuo at the level of the sea, the temperature being 
50° of Fahrenheit at Port Bowen, in latitude* 73° 13' 39". N, 
longitude 88 ° 54' 48" W, and are as follows : 
By the observation of disappearance - 86230,147 
By the mean of disappearance and re-appear. 86230,288 
The state of the ice in the offing being such, as to indicate 
no immediate prospect of the ships leaving Port Bowen, I 
gladly availed myself of Captain Parry’s permission to 
pursue these observations by another series ; the difference 
between the results of which, and those of the first series, being 
only 0.105 of a vibration in 24 hours, affords, it is presumed, 
* The elements of the observations for the latitude, and longitude, are given in 
the Appendix to the Narrative of Captain Parry’s Third Voyage for the Disco- 
very of a North-West Passage. 
