TWENTY-FOUBTH ANNUAL 3IEETIN0. 



59 



there is a deficiency of temperature during a part of the year, there must be an ex- 

 cess of the same amount of temperature daring the remaining part. 



It is the object of this investigation to determine, from Prof. F. H. Snow's tem- 

 perature record for Lawrence, the degree of certainty with which we may predict 

 the temperature of the summer vacation at that place. To those of us who go to 

 the mountains and various other places, to escape the hot weather of July and Au- 

 gust, this subject is of interest. 



The three summer months, June, July, and August, form the third quarter of the 

 year. It will serve best our purpose to have the summer the last quarter. The 

 summer will then be at the end of our year, and we can thus better predict its tem- 

 perature. We have, therefore, divided the record so as to have the first of Septem- 

 ber the beginning of each year. The annual temperatures computed from this 

 division do not differ much from those computed with the year beginning on the 

 1st of January. 



The numbers in columns 1, 2, 3 and 4 need no explanation. Any number in col- 

 umn 5 is gotten by subtracting the number opposite to it in column 2 from the 

 mean at the foot of column 2. The numbers in columns (i and 7 are gotten from 

 those in columns 3 and 4, in the same way that the numbers in column 5 are gotten 

 from those in column 2. A plus variation means temperature above the mean or 

 normal, and minus variation means temperature below the normal. 



Examining the numbers in columns 6 and 7, and comparing those for the same 

 year with each other, we see that there are 12 with like signs and 11 with unlike signs. 

 We see that of these 12 with like signs four only are such that both the numbers are 

 greater than .88°. Of these four numbers, after each of which I have placed a star, 

 three have minus signs and one a plus sign. Remembering that variations with like 

 signs in columns 6 and 7 signify a failure to predict correctly the summer tempera- 

 ture, we see that in the 23 years covered by this record about one-half the predic- 

 tions in regard to whether the summer temperature will be above or below the 

 normal would fail,. Of these 12 failures, four only are bad failures {i. e., temperature 



