310 KANSAS CITY REVIEW OF SCIENCE. 
II. On a certain occasion, having successfully performed the well-known 
experiment of producing jets of flame in the bottom of a tube of water containing 
bits of phosphorus and potash chlorate, I concluded out of curiosity to add to 
the mixture a few scales of iodine. Having done this I placed the tube over the 
spirit lamp, when there occurred quite a violent explosion — a part of the water in 
the tube being thrown out, and at the bottom of the tube there remained a 
spongy mass, brown in color, and several times greater in bulk than the aggre- 
gate of the three solids originally put into the tube. The query is : what was the 
chemical reaction in this experiment ? And again, since iodine and phosphorus 
readily burn in air if in contact, did the presence of a small quantity of sulphuric 
acid help to produce the result ? 
I would like very much to have answers to these queries through the Re- 
view or otherwise. 
III. A barometer, much more reliable than the "storm-glass" which has 
had such extensive sale during the past few years, may be made as follows : Let 
one end of a glass tube, one half inch in diameter and about twenty-eight inches 
long, be corked air-tight, then fill the tube about four-fifths full of water, insert 
the open end in a large mouthed bottle or a glass fruit jar. On a piece of paper 
mark a scale in inches and tenths and attach it to the outside of the tube, having 
the middle of the scale even with the top of the water in the tube. The scale 
need not be over four inches in length as that will more than cover the rise and 
fall that will be observed. The instrument is now complete, but correction for 
temperature must be made for each observation, as the height of the column of 
water varies much more from changes in temperature than from atmospheric 
pressure. With the instrument which I have constructed on this plan the de- 
pression of the column for each degree of increase of temperature is .036 inches. 
Let the following, taken from two observations on the 20th of last July, serve to 
show correction for temperature : 
Thermometer 2 P. M '. .78° 
Thermometer 9P. M. . .. . . . . . .72° 
Water Barometer 2 P. M 12.45 inches. 
Water Barometer 9 P. M 12.55 inches. 
78°— 72°=6°. .036X6=. 2 1 6, say .22. 
12.45-}-. 22^12.67. 12.67 — 1 2. 55=. 1 2. 
It may be understood from this that had there been no change in the atmos- 
pheric pressure the barometer reading for the latter observation would have been 
12.67, but since it stood 12.55 it indicated a depression of .12 inches on the 
column of water. 
Having compared the workings of this simple instrument with a number of 
standard ones, I am satisfied that it is worth the trouble of construction. The 
material would cost but twenty-five cents, and the making would require less than 
as many minutes. The tube should pass through the cork but of course the 
bottle should not be corked air-tight. After the water has remained in the bottle 
