104 KANSAS CITY REVIEW OF SCIENCE. 



be a compromise, as it were, between the north winds and the south winds, the 

 result of which will be a medium temperature. 



These statements are not mere theories nor ideal conceptions, but substantial 

 facts, which can no more be disproved than that water will run down hill, or that 

 combustion will produce heat. 



But what about that snow storm in Chicago on the morning of the 19th of 

 March, when Mr. Vennor said that about the 20th of March or thereabout, there 

 would be a great snow storm in the " lake region," and that, too, said some weeks 

 in advance, when on the very morning of the 19th of March, the weather bureau 

 said that the indications for this region were for fair weather. 



At first it certainly appears that the weather prophet was at least right that 

 time, and that the weather bureau, to say the least, committed a most awkward 

 blunder. But before we commit ourselves, let us weigh well the facts m the case, 

 and consider well the causes which produced the snow storm. 



In the first place, the Signal Office takes three observations daily — at 7 a.m., 

 3 and 1 1 p. m. 



An average speed of low is about three hundred and fifty to four hundred 

 miles in twenty-four hours. When the storm center low is at St. Louis on one 

 day, on an average, on the morning of the second day thereafter it will be at 

 Washington. 



There is, however, no regularity about the speed of low, for sometimes it 

 will even go from the base of the Rocky Mountains to the Atlantic coast in twen- 

 ty-four hours. But these instances of great speed are exceptions. I only men- 

 tion this irregularity of speed to show that there is no knowing before hand, at 

 least at present, the rate at which it will travel. As little can we know in ad- 

 vance the direction it will take. And this illustrates one of the greatest difficul- 

 ties with which the signal office has to contend. They see a storm in the west. 

 What time will it reach the meridian of Washington ? If they give out an " indi- 

 cation," it must be founded upon the average and not upon the exceptional speed. 

 Again, if a low is in the west, what course will it take ? This is fully as impor- 

 tant as the speed. It may keep on a straight line and follow a line of latitude in 

 its course, or trend more or less to the north as it advances east. 



On the morning of the *8th of March, low was in the extreme southern por- 

 tion of Texas, with the center even still further to the west, or southwest, but 

 'Owing to the want of stations in this region we cannot tell exactly where the cen- 

 ter was, but we do know that it was somewhere beyond Brownsville. 



The morning reports for the press must be made up at midnight — to accom- 

 modate all parts of the country, one will see that the reports could not be much 

 later. 



At ri o'clock on the night of the i8th of March, low had advanced up into 

 Mississippi. 



These southwestern lows had, prior to this, traveled within certain lines, or 

 probably better, traveled within a certain arc. They had either gone straight 

 across the country, passing off the land on the Florida coast, or in their passage 



