September 17, 1891 J 



NATURE 



473 



not thoroughly equipped great caution in publication." (3) The 

 Construction of a Natural Syitem.-'Wv^ speaker spoke of the 

 necessity of constructing a natural system with easy advance in 

 the knowledge of affinities, as a convenient summary of informa- 

 tion, a sort of mile-post, to tell of progress and to direct future 

 effort. The concluding summary was as follows : — " The points 

 presented in this consideration of the third phase of systematic 

 botany are that the last and highest expression of systematic 

 work is the construction of a natural system, based upon the 

 accumulations of those who collect and describe, and those who 

 study life-histories ; that this work involves the completest com- 

 mand of literature and the highest powers of generalization ; 

 that it is essential to progress for a natural system to be at- 

 tempted with every advance in knowledge ; and that all the 

 known facts of affinity, thus brought within reach, should be 

 expressed in all systematic literature." 



This Section, as usual, was the most crowded of all, forty- 

 seven papers having been read before the Section itself, and 

 many more before its two offshoots, the Botanical and the 

 Entomological Club. This was another of the Sections which 

 its Secretary considered to have had the most successful meeting 

 on record. A feature now at every annual session is the report 

 of members appointed the year before to study certain assigned 

 questions. This year four such reports were presented : — Trans- 

 piration, or the loss of water in plants, was treated by Chas. E. 

 Bessey and Albert F. Woods. "Movements of fluids in plants " 

 was read by Prof. Wm. J. Beal, of Michigan. Dr. J. C. 

 Arthur, of Purdue University, Lafayette, Ind., read a paper 

 entitled "Gases in Plants." A paper was read by Prof. L. H. 

 Pammel, of Ames, Iowa, on the absorption of fluids by plants. 



Section H — Anthropology. 



The youngest Vice-President at this session, if not the youngest 

 man who ever held a Vice-Presidential office in the American 

 Association, is Prof. Joseph Jastrow, whose age is 28 years. 

 His address was entitled " The Natural History of Analogy." 



Major J. W. Powell, Chief of the U.S. Geological Survey, 

 exhibited and explained his linguistic map of North America, 

 on which he showed the classification of languages of the 

 aborigines. 



Mr. Gushing read a paper on the Zuiii Indians, and danced 

 the Messiah dance, which a few months ago was so much talked 

 about, and almost involved a war with the Government. 



Section I — Economic Science and Statistics.. 



Of all the Vice-Presidential addresses, that of Prof. Edmund 

 J. J.ames, of Philadelphia, before this Section, aroused the most 

 widespread popular interest and attention, on account of the 

 vital practical importance of the theme presented, which was 

 "The American Farmer: his present economic condition and 

 future prospects." 



The silver question was carefully considered, and all who 

 took part in the discussion agreed in opposing the free coinage 

 schemes which are now so vehemently urged upon Congress. 



The general business of the Association included a change in 

 the constitution, so as to admit fifty foreign honorary members, 

 and many recommendations to Congress as to forestry, water 

 supply and management, and other topics. Preliminary arange- 

 ments were made to participate in the Columbian World's Fair 

 in 1893. A Committee was appointed to solicit donations for the 

 endowment of the Association with a fund of at least §100,000. 

 Three hundred and seventy-one ncA' members were elected, 

 bringing the total membership up to about 2300, which is high- 

 water mark in the history of the Association. 



Prof. Joseph Le Conte, of California, was elected President ; 

 and the Association adjourned, to meet at Rochester, N.Y., on 

 the third Wednesday of August 1892. 



RAIN-MAKING IN TEXAS. 



'T^HE announcement in the Standard about a fortnight 

 -*■ since, that rain had been artificially produced in 

 Texas by exploding oxyhydrogen balloons and dynamite, 

 was probably received by most scientific men with a sus- 

 pension of judgment. The somewhat sensational form 

 of the report, the emphasis with which it dwelt on the 

 unfavourable antecedent conditions, and the omission of 



NO. I 142, VOL. 44] 



all details that might enable us to form some rough esti- 

 mate of the forces employed and of the resulting effects, 

 seemed calculated to appeal to the barren emotions of 

 astonishment and love of the marvellous rather than to 

 the sober judgment of well-balanced minds ; and but for 

 the fact that the experiments were stated to have been- 

 made by the officers of the U.S. Signal Service, which^ 

 on the hypothesis of a hoax, would have been a needless 

 challenge to speedy denial, one might have been disposed 

 to regard the story as only an additional instance of a 

 kind of produce for which the Western States are some- 

 what notorious. The further accounts that have now 

 reached us prove, however, that this is not one of 

 Jonathan's amusing attempts to play off on the cre- 

 dulity of his simple-minded cousins across the Atlantic. 

 Not only have experiments of the kind described been 

 actually made, but they have been apparently successful, 

 and they seem to have been repeated sufficiently often to 

 render it at least improbable that this success has been 

 entirely fortuitous. The improbable features of the 

 Standard's report are, indeed, somewhat toned down ;; 

 the dryness of the local atmosphere was by no means so- 

 great as was to be inferred from the vague language of 

 the Standard's informant ; but, as far as can be judged 

 from the notices now before us, it seems unlikely that the 

 rain which followed General Dyrenfurth's experiments 

 would have occurred in the undisturbed course of natural 

 events. 



The experiments were made at a place known as 

 Ranch C. One writer states that an intermittent series 

 of experiments had been carried out for three weeks, and 

 that " not in a single instance has rain failed to fall within 

 ten or twelve hours after the explosion." But the number 

 of trials is not stated — an omission the more to be re- 

 gretted, because the improbability that the results are 

 fortuitous increases in a certain geometric ratio of the 

 number of successful repetitions. We have definite ac- 

 counts of those made on August 18, 26, and apparently 

 the morning of the 27th, and it is by no means clear 

 that the evidence is not limited to these, although the 

 expression quoted above would seem to imply otherwise. 

 The first, that of August 18, was made about 3 p.m. 

 There were at the time a few scattered clouds, but no 

 indication of rain. The reading of the barometer is not 

 reported, but the relative humidity of the air immediately 

 before the experiments (presumably at the earth's surface) 

 was not more than 60 per cent, of saturation. An oxy- 

 hydrogen balloon, the capacity of which is not stated, 

 was exploded by electricity at an altitude of a mile and 

 a quarter. Several kites, with packets of dynamite at- 

 tached, were sent up immediately after the balloon, and 

 the charges exploded by similar means, and " rendrock 

 powder was distributed for a distance of two and three- 

 quarter miles from head-quarters, and fired by igniting 

 dynamos." These explosions " sent up great volumes of 

 white smoke, which rose only a short distance, and was 

 then beaten down by heavy rain, which at once began 

 falling and continued for four hours and twenty minutes." 

 Prof. Curtis, the meteorologist of the expedition, esti- 

 mates that the rain covered an area of not less than 1000 

 miles. 



On August 26 it is stated that " balloons containing 

 several thousand feet of oxyhydrogen gas were sent up 

 and exploded at heights varying from 1000 to 10,000 feet, 

 and at sundown batteries on the ground began their 

 work, and until 10.30 p.m. a constant cannonade was 

 carried on under a sky of perfect clearness, lit by count- 

 less stars of a brilliancy seldom seen in the north. The 

 barometer promised fair, and the hygrometer stood 

 between dry and very dry," whatever these expressions 

 may mean. The account continues : — " At 1 1 p.m. General 

 Dyrenfurth withdrew his forces, and all retired for the 

 night. Sleep, however, was soon interrupted, for at 

 3 a.m. the first return fire flashed from the heavens, when 



