52 LANDS OF THE ARID REGION OF THE UNITED STATES. 
comprising stations in the Region of the Plains all the way from our 
northern to our southern boundary. By way of restricting attention to the 
practical problem of the limit of “dry farming” 
, only those stations are 
admitted which exhibit a mean annual rainfall of more than 15 and less 
than 25 inches. The order of arrangement is by latitudes, and in the 
columns at the right the seasonal rainfalls are expressed in percentages of 
the yearly. The column at the extreme right gives the sum of the spring 
and summer quotas, and is taken to express the availability of the rain- 
fall. 
TABLE VII.—Seasonal precipitation in the Region of the Plains. 
| 3 a Percentages of annual rainfall. | 
| S12. | E 
Station. | iS 4 E rc | 3 | 5 F ies a | 
es + ye bob) ee 8) 8 |}wa 
4 ag |a ala |4]-E |e) 
° Y.M. | Inches. | 
TECHN Ob TOW ee eines Sask bam RHSe eer aaaob and case pes arcs esses 48 57 4 8) 15.50 26 ay aly 10| 73 
| Fort Totten, Dak 4756| 5 5| 16.44] 31] 44] 15| 10] 75 
| Fort Abercrombie, Dak 27| 13 6| 18.78| 26| 46] 18| 10] 72| 
Fort Wadsworth, Dak -.- 6 5| 24.15| 29) 42] 17| 12| w 
It Ste IDA 6 ps peat sees se See SOarOSe mice Debacou so -cceneaSsooe 7 8| 16.54 39| 44) 10 7 83 | 
Salus GMURN S425 toe shoes Sonos senda tocoset sess gescscossensgacs gf bil 24, 74 21 40 | 29 10 61 | 
MontpbandalliMalcqees osceee se eae scenes es coke ee ue ean 15 6| 15.52] 30| 40] 22| 8| 70| 
THOT EVUCIS ODS OM NG DT ete ee ate ete ale fe eel eee otter 6 18.96 | 36 40) 17 7 | 76 | 
| = ———- = = - > ] i > ae a lees Se 
Fort Riley, Kans. ..-.--.. oaDANE Ee And ROU SabBULSSE SHS Seeacapne SR ouESe 2010) 24.52 22 43 24 11 65 
Fort Hays, Kans--....-.. 6 11 22. 70 31 27 25 17 58 
iy rd BE rarGG VEN cin aS aor en sas bao Sea mSaod Seber a Ace SseasmecasasoS | 10 9) 21.42 24 45 23 8 69 
if 
= ia ee ee = ae 
Fort Griffin, Tex... --- f 5 3] 2151) 23 29 29 19 | 2 
Fort Chadbourne, Tex - F 8 | 8 7 | 22.88 | 25 29 31 15 54 | 
IUCN E Hit ALES Sahoo cos aeeseno sss Svea e soccer mSccgo eon ces 30 48 9 7] 23.95 22 28 32 18 50 
WAMon Oats, IU cscs ascsSoss ain cOapee oS aoSads Sones Soon ---.--| 30 40 8 11 yeah 3b 51 28 10} 62 
Fort Clark, Tex.-...:---.- 29 17 12 5 22. 61 | 18 34 29 19 | 52 | 
Fort Duncan, Tex...-.. 28 39) 11 7 | 21.33 7 40} 31) 12 | 57 
Fort McIntosh, Tex.....- 2735 || 14.7 17. 51 | 18 88) — 31 13 56 
Ringgold Barracks) Lex.---- co. aniscae eee ocean cisely 26 23; 14 2) 19.60 19 36 32 13 55 | 
\ 2 | 
The graduation of the ratios from north to south is apparent to inspec- 
tion, but is somewhat irregular. 
The irregularity, however, is not greater 
han should be anticipated from the shortness of the terms of observation 
at the several stations, and it disappears when the stations are combined in 
natural groups. 
Dividine the whole series into three groups, as indicated 
as] ? 
