TRANSACTIONS OF TIIE SECTIONS. 
567 
free exposure to the intense light evolved by lime, under the 
action of the hydro-oxygen blowpipe ; but no differences were 
observed in the time of vibration on the arc, previously de¬ 
termined in the shade. We may hence infer, that mere light 
has but little influence on the oscillations of a magnetic needle. 
The author arrives at the same conclusion in respect of free 
electricity pervading a vacuum, which, flashing brilliantly 
through an exhausted receiver, 6 feet high and 4 inches in dia¬ 
meter, during the space of 25 minutes, and within a foot of the 
needle, did not in any way affect its rate or arc of vibration, 
whilst the needle oscillated in vacuo. 
The author is impressed with the conviction, that many of 
the uncertainties which at present embarrass the observer in 
taking magnetic intensities, may be fairly traced to some of the 
above-mentioned causes ; and expresses a hope that when the 
object of taking these intensities is considered—no less a one 
than the accurate measurement of the earth’s magnetism—the 
few attempts which he has thus made to improve our methods 
of research, will be of advantage to this important department 
of science. 
An Account of some extraordinary effects of Lightning on the 
Packet Ship , New York, By the Rev. W. Scoresby, F.R.S. 
The circumstance to which this paper refers, occurred on 
the passage of the New York packet from America to Liver¬ 
pool in the year 1827. Soon after the commencement of the 
voyage, this vessel encountered a severe thunder-storm, and re¬ 
ceived a stroke of lightning which shattered the masts in seve¬ 
ral parts, and started some of the exterior planks of the bends. 
This was in the morning before daylight. The weather con¬ 
tinuing unsettled, and the air in a highly electric state, with 
water-spouts in various directions around—the captain, fearing 
another explosion from the highly charged atmosphere, put up 
a lightning conductor which he had on board. In the after¬ 
noon of the same day, the ship was a second time struck, but 
preserved by the conductor, though the iron of which it was 
composed was destroyed, and fell in melted globules upon the 
deck. No lives were lost, though some of the crew received 
heavy shocks : whilst one person, an invalid passenger, de¬ 
rived essential benefit from the electric discharge. Mr. Scores¬ 
by had an opportunity of examining the vessel immediately on 
her arrival in Liverpool, when, on investigating the condition 
of the iron on board, he found almost every article capable of 
