OVER A WIDE EXPANSE IN AMERICA. 101 



deficiency was to such an amount as to endanger a due supply to the 

 city for the current year. And not only this, it has also been 

 asserted that, for several years past, there has been a steadily 

 occurring diminution in the rainfall. Whilst the quantity of water 

 has thus been becoming less and less, the demand has been becoming 

 greater. Not only has the population of the city increased, but also 

 that of the suburban districts, which derive their supplies from the 

 same water-gathering grounds that we do. 



" I therefore supposed, since our registering rain-gauge furnishes 

 very reliable measures, that it would be useful to examine this sub- 

 ject critically. But since we have had these gauges in operation only 

 about three years, and as the investigation proved to be full of 

 interest, I was led to draw upon other additional sources of informa- 

 tion, selecting such as seemed to be of the most trustworthy kind. 

 By the aid of these, the examination has been extended as far back 

 as 1836, and with the following results: — 



" 1st. As respects the indications given by our own instruments, 

 which may be thoroughly relied on for the years 1869, 1870, 1871. 



" For the first of these years, 1869, the total rainfall was 46-82 

 inches, distributed as follows : During the first quarter, 15-06 inches; 

 second quarter, 10-24 3 third quarter, 7-72; fourth quarter, 13-80 — 

 total, 46-82. 



" For 1870, the total rainfall was 42-32 inches, distributed as 

 follows: During the first quarter, 12-86 inches; second quarter, 

 10-29; third quarter, 9-39; fourth quarter; 9-78 — total, 42-32. 



For 1871, the total rainfall was 52-06 inches, distributed as 

 follows: During the first quarter, 10-33 inches; second quarter, 

 14-12 ; third quarter, 14-21 ; fourth quarter, 13-40— total, 52-06. 



" So far as these years are concerned there does not appear any 

 evidence of a decrease. On the contrary, in the last there is a very 

 considerable excess over either of the others. 



" Extending our examination to preceding years as far back as the 

 beginning of 1836, and grouping those years into three periods each 

 of ten, and one of six years, the statement comes to this : First 

 period, from 1835 to 1846, 39-5 inches ; second period, from 1845 to 

 1856, 47-0; third period, from 1855 to 1866, 52-0; fourth period, 

 from 1865 to 1872, 52-0. This would make the annual rainfall 

 throughout these 36 years, 47-62 inches. That of the last three 

 years 47-06. 



"These numbers being substantially the same, it may be con- 

 cluded that, though there are large variations from year to year, aa 



