528 
Carbons in the Electric Lamp. 
[August, 
with milder forms of neuralgia, and are not felt until the 
storm centre is nearer. Rain is not essential in the produc- 
tion of neuralgia. 
It was found that the severest neuralgic attacks of the 
year were those accompanying the first snows of November 
and December. One of the most interesting and valuable 
results of this series of observations is thus stated : — “Every 
storm, as it sweeps across the continent, consists of a vast 
rain area, at the centre of which is a moving space of 
greatest barometric depression, known as the storm centre, 
along which the storm moves like a bead on a thread. The 
rain usually precedes this by 550 to 600 miles, but before 
and around the rain lies a belt which may be called the 
neuralgic margin of the storm, and which precedes the rain 
about 150 miles. This fact is very deceptive, because the 
sufferer may be on the far edge of the storm basin of baro- 
metric depression, and see nothing of the rain, yet have pain 
due to the storm. — Kansas City Review of Science and 
Industry. 
IV. A METHOD OF PREVENTING THE 
TOO RAPID COMBUSTION OF THE CARBONS 
IN THE ELECTRIC LAMP. 
By H. W. Wiley. 
N using the electric light for projections two chief 
points are to be considered, viz., 1st, brilliancy of 
illumination, and 2nd, steadiness of the light. When 
the source of electricity is sufficient the first of these ends 
is easily obtained. The second, however, is not so easy of 
accomplishment. The chief difficulty in the way of securing 
steadiness is found in the carbons themselves. Some car- 
bons, and I find these to be the most common, burn away 
so rapidly that, where no mechanism is present to produce 
alternating currents, the electric arc is constantly passing 
out of the focus. Often, too, I have found that when the 
current is quite strong with the softer carbons, the arc 
would extend itself momentarily between points as far as a 
