October 27, 1905.] 



SCIENCE. 



527 



A special meeting of this taxpayers' protective 

 association has been called to be held this evening 

 at 7:30 o'clock. * * * 



' The passage of the proposed ordinance,' said a 

 prominent taxpayer this forenoon, ' would be noth- 

 ing short of an outrage.' 



I wonder what this ' prominent taxpayer ' 

 thinks about the ordinance now. It is a sad 

 thing to suggest, but possibly he himself or 

 some member of his family has died as a 

 result of the senseless opposition, in which he 

 took part, to a reasonable and public-spirited 

 health measure. 



In an evening paper of March 28, 1902, 

 there appeared a note to the effect that a cor- 

 respondent of the Associated Press had a talk 

 with the State Health Officer of Texas, re- 

 garding the mosquito theory. He was re- 

 ported as of the opinion that ' The theory 

 won't hold water,' and stated that he would 

 not accept it. He stated that he had been 

 familiar with yellow fever from childhood 

 and ' knew enough to keep rigid quarantine 

 and disinfecting rules in effect.' A little more 

 than a year later, however, he had a new lesson 

 in the Texas outbreak of yellow fever in the 

 late summer and autumn of 1903, and he too 

 changed his mind in regard to mosquitoes. 



L. O. Howard. 



THE POSSIBILITY OF ABSORPTION BY HUMAN BE- 

 INGS OF NITROGEN FROM THE ATMOSPHERE. 



Any one reading this article would conclude 

 that it has been proved that plants can absorb 

 free nitrogen from the atmosphere without 

 the aid of bacteria, and that Dr. Wohltmann 

 is a believer in this. The quotation which 

 the writer gives does not bear out this inter- 

 pretation of Dr. Wohltmann's work: 



The association of the plant with the bacteria 

 is not a necessity but an expedient, and when- 

 ever there is a rich supply of nitrogenous elements 

 in the soil, they (the plants) dispense with the 

 bacteria and icith the free nitrogen, which the 

 latter make available, by directly secreting it 

 from the chemical combination of soil or air in 

 which it is held suspended. 



The italics are mine, but the translation is 

 by Mr. Gibson. Dr. Wohltmann is far from 

 saying that plants absorb free nitrogen in the 



absence of bacteria; but distinctly says, in the 

 above quotation, that in the absence of the 

 bacteria they dispense with the free nitrogen 

 and take the nitrogen necessary for their 

 growth in combination from the soil. 



This is no new discovery, for Hellriegel, in 

 1886 and later, showed by decisive experiments 

 that when the bacteria are absent, Legumin- 

 osse, like other plants, can only take their 

 nitrogen in compounds, and their growth, 

 within limits, is a function of the corabined 

 nitrogen presented. In the presence of bac- 

 teria Leguminosse can utilize the free nitrogen 

 of the air, and build it up into organic com- 

 pounds. 



Before speculating on the possibility of the 

 absorption of free nitrogen by human beings, 

 it is well to remember that there is no evidence 

 that higher plants can assirailate nitrogen of 

 the air without aid of bacteria. 



G. S. Traps. 



A tree's limb without bark. 

 To the Editor of Science: In the summer 

 of 1902 a large ash tree, some two feet in diam- 

 eter, on the university campus was struck by 

 lightning. The current, after knocking off a 

 few branches, passed down on both sides of the 

 main trunk leaving here merely two small 

 furrows in the bark. Trom one limb, some 

 six inches in diameter and perhaps ten feet 

 from the ground, the bark all around was 

 completely stripped for a distance of about 

 five feet. To the surprise of some of us the 

 leaves on this branch did not wither, nor fall 

 to the ground till the leaves of the rest of the 

 tree fell in the autumn. The next spring the 

 leaves put out on this branch as on the rest of 

 the tree; so again in 1904 and again the pres- 

 ent year. In other words, the vegetation of 

 this branch, wholly girdled for a space of sev- 

 eral feet, differs from that of the rest of the 

 tree only in being slightly less vigorous. The 

 wood of the girdled portion looks much like 

 a seasoned log of ash wood. The tree itself 

 is rather less vigorous than the neighboring 

 ashes, and will probably survive but a few 

 years longer. Is it common for a limb. 



