jAiNlAHY 27, 1905.] 



SCIENCE. 



151 



is a poor sizing agent, and that the base of 

 the precipitating agent plays a very important 

 part in sizing paper. Incidentally he shows 

 that any reagent whose base is alkaline will 

 not effectually size paper, no matter how com- 

 pletely the rosin may be precipitated in com- 

 bination with it. 



The Tensile Strength of Bronzes. Wilder D. 

 Bancroft. 



The tensile strength of the copper-tin 

 bronzes containing more than 92 per cent, 

 copper varies relatively little with the different 

 heat treatments. With bronzes containing 

 75 to 92 per cent, copper the strength is much 

 greater if the alloy is quenched from above 

 500° than if it is quenched from below 500°. 

 The extreme effect is to be found with the 

 79 per cent, bronze, which has a tensile 

 strength, of oyer 70,000 pounds per square 

 inch if quenched from low red heat and a 

 strength of only about 30,000 pounds per 

 square inch if quenched from 400°. Similar 

 results were obtained with the ductility meas- 

 urements, though the maximum ductility does 

 not occur at the same concentration as the 

 maximum strength. The bronze containing 

 90 per cent, copper gives a 40 per cent, elon- 

 gation if quenched from 540°, and only a 

 10 per cent, elongation as cast. This work 

 has been made possible by a grant from the 

 Carnegie Institution. 



The Production and Modern Uses of Carbonic 



Acid. John C. Minor, Jr. 



The paper describes the causes leading to 

 the development of the carbonic acid industry, 

 taking up the different methods of production, 

 viz., calcination, acid treatment of carbonate, 

 fermentation, the coke process, and the meth- 

 od used at Saratoga Springs for securing COj 

 from the natural mineral waters there. The 

 treatment of the gas after production and the 

 cylinders for holding it under high pressure 

 are discussed. Among the commercial uses 

 for CO, described at some length are men- 

 tioned : the manufacture of carbonated bever- 

 ages, the extinguishing of fires on shipboard, 

 the drawing of beer, the use in breweries for 

 replacing the secondary fermentation, refrig- 

 eration, the operation of block signals, and the 



extraction of logwood. The therapeutic uses 

 of CO2 are also indicated. 



F. H. POUGH, 



Secretary. 



THE TORREY BOTANICAL CLUB. 



The regular meeting of the club was held 

 December 13 at the College of Pharmacy, 

 Dr. H. H. Eusby in the chair, eleven members 

 present. 



The first paper on the program was by Pro- 

 fessor r. E. Lloyd, who spoke of the Desert 

 Botanical Laboratory at Tucson, Ariz. He 

 pointed out that there were four characteristic 

 types of desert visible with great regularity 

 from the car window westward from El Paso, 

 as the train passed from mesa to hill country 

 or vice versa. 



The character plants of these four deserts, 

 which are remarkably distinct and pure, are 

 the Yucca, Ephedra, Mesquite, Parkinsonia 

 and Fouquieria in abundance. Professor 

 Lloyd spoke in some detail of the vegetation 

 in the vicinity of Tucson, illustrating his re- 

 marks with numerous excellent photographs, 

 including several good pictures of Cereus gi- 

 ganteus in bloom and in fruit. 



It was remarked that the plants with motile 

 leaves, such as Cassia, Acacia and Parkinsonia, 

 all faced the sun at sunrise, but did not follow 

 its course during the day. Fouquieria was 

 described in detail, attention being called to 

 its short-lived primary leaves and curious 

 spines, which were cited as an example of 

 direct metamorphosis, the rosettes of secondary 

 leaves appearing in the axils of the latter. 



The primary object of Professor Lloyd's stay 

 at the laboratory was the determination of 

 the relation between stomatal action and trans- 

 piration. Numerous experiments were made, 

 the results of which are to be reported in de- 

 tail later. 



The second paper, by George V. Nash, was 

 on the vegetation of Inagua. Mr. Nash re- 

 cently spent four weeks in collecting there. 

 Inagua includes a large and a small island 

 located some sixty miles northeast of Cuba, 

 and with a total area of between five and six 

 hundred square miles of mostly low land, the 



