49 
barograms, traced in 1890 near American tornadoes, came to 
my hands. Two of these were made during the great Louisville 
Tornado, on March 27th. The three are now reproduced 
photographically from the enlarged cuts in Science^ kindly 
photographed by J. P. J. Malcomson, of Bootham School. 
Fig. 4. 
Midn Noon Midn. Noon 
With them is a micro-photograph, kindly made by Thomas H. 
Waller, B.A., B.Sc., of Birmingham, of the tracing at Bootham 
School, distant 2^ miles from the centre part of the wind-rush. 
The comparison, it will be seen, is with the Cincinnati curve. 
Fig. 5. 
Midn Noon Midn Noon 
not that at Owensborough. The former is a wedge-shaped 
rise and fall^ the rise of about 0T6 inch, the fall of OT inch in 
a straight line, changing by a steep curve of O'04 inch into a 
gentle fall of 0'03 in IJ hours. There had previously been a 
rapid fall of 0T5 inch in 1| hours. The York micro-photograph 
