DIMINUTION OF THE WATER OF RIVERS AND STREAMS. 203 



decrease of evaporation, and the proinotiou of a regular escape of the 

 precipitation is evident, while the disadvantageous results of their 

 removal is felt in the prolonged i)eriod of dryness on the one hand, 

 and the destructive high water on the other. 2d. In the desiccation 

 of the lakes, ponds, and bogs, which likewise raises the hygroiuetric 

 conditions, decreases evaporation, moderates extreme temperature, and, 

 lastly, through the fissures in the soil, directly promotes the formation 

 of springs, od. In the cultivation of extended tracts of land, for the 

 irrigation of which large quantities of water are required. 4th. In the 

 increase of the i)opulatiou and the domestic animals, although the dim- 

 inution of the water from this cause is relatively so small as to be 

 unimportant, oth. Lastly, it seems to the commission that, in accord- 

 ance with the opinion expressed by M. L. Saemann, that water is con- 

 tinually absorbed in the interior of the earth, in the formation of mine- 

 ral substances into which it enters as the water of crystallization, this 

 telluric cause of the decrease of water is worthy of consideration. 



The commission concluded, in view of the data published by Mr. Wex, 

 to support the recommendations he also gives in his report, as follows: 



1st. That the Eoyal Academy of Science shall call the attention of the 

 Austrian government, and of the royal commercial and agricultural ad- 

 ministrations, to theestablished fact of the continual decrease in the water 

 of springs and streams, and also to the causes of this phenomenon, and 

 endeavor to induce these high authorities to take into serious consider- 

 ation the modes of record and the i)reventive measures proposed by Mr. 

 Wex to check this deterioration, which threatens with dire calamity 

 future generations, |ind induce them, by the i)ublication of suitable rules 

 and regulations, to secure the accomplishment of the end to be desired. 



A similar effort should be made by the Royal Academy of Science to 

 bring this subject to the knowledge of the countries belonging to the 

 Austrian crown, which have in late years been more than ever occujjied 

 in the clearing out of under-brush, the drainage of lakes, swam[)s, and 

 moors, and, lastly, in the damming up of regions formerly inundated by 

 the floods which, appearing with constantly-increasing frequency, must 

 be accompanied by c()rresi)onding periods of drought and uufruitfulness. 



li. The Itoyal Academy of Science should send to the scientific insti- 

 tutions of other countries, namely, Holland, England, France, Italy, 

 Spain, IJussia, North America, and Brazil, a copy of the memoir of Mr. 

 Hofrathes Wex, with the recpiest for communications of the yearly obser- 

 vations of the water-heights of the rivers of the difi'erent countries. In 

 this way water-height observations might be obtained which have not 

 been i)ublished, abstracts of which might be made and graphically rep- 

 resented, as in the nuunoir Just mentioned. 



3. Especially should th(^ government of the viceroy of Egy])t be 

 advised of the wish ol" the lioyal Academy, so that of the observations 

 of the water-heights of the Nile above Cairo, continued for oOO years, a 

 copy, at least of those of the last 200 years, might be obtained, with 

 similar tables and graphical representations. 



