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THE POPULAR SCIENCE MONTHLY 



them only by referring them to some cen- 

 tral organization and direction like the 

 newly established institute. 



Action of Citric Acid on Minerals. Pro- 

 fessor H. C. Bolton read a third paper at the 

 recent meeting of the American Association 

 on the decomposition of minerals by citric 

 acid, detailing the results of his later re- 

 searches on the subject. Some of the con- 

 clusions expressed in the first of his two 

 previous papers were modified in the sec- 

 ond paper, in view of the results obtained 

 by the prolonged action of the acid. In 

 the third series of experiments Professor 

 Bolton found that many species which re- 

 sist the brief action of a boiling concen- 

 trated solution of citric acid are more or 

 less completely decomposed by prolonged 

 contact with the same solution at the ordi- 

 nary temperature of the work-room. He 

 has drawn up a table, in accordance with 

 the last series of tests, of thirty-two min- 

 erals or classes of minerals which are classi- 

 fied as those that are quickly, slowly, very 

 slowly, or not, decomposed by citric acid. 



In an American Association paper Dr. 

 Britton describes a Post-Tertiary, pre-glacial 

 deposit, near Bridgeton, New Jersey, com- 

 pact enough to furnish a building material, 

 which contains casts of the shells of the 

 hard clam, with silicified wood, and in which 

 very fine impressions of leaves including 

 those of the sweet-gum, or liquidambar, vi- 

 burnum, zizania, and elm are occasionally 

 found. 



NOTES. 



According to the Census Bureau's bul- 

 letin of the statistics of the lumbering in- 

 dustry of the United States for the year 

 ending with May last, $181,186,122 are in- 

 vested in 25,708 establishments for the prep- 

 aration of lumber, and the total value of 

 the products for the year was $233,367,729. 

 Michigan leads the States in this industry 

 with 1,649 mills, $39,260,428 capital, and 

 $52,449,928 of products. Pennsylvania is 

 second, with 2,827 mills, $21,418,588 of 

 capital, and $22,457,359 of products. Next 

 are Wisconsin, with $19,824,059 of capital, 

 and $17,952,347 of products; New York, 

 $13,230,934 of capital, and $14,356,910 of 

 products ; and Indiana, with $7,048,088 of 

 capital, and $14,260,830 of products. Maine, 

 which used to be considered emphatically 

 the " lumber State," is now seventh in rank, 



having 848 mills, with $6,339,396 of capi- 

 tal, and $7,933,868 of products. 



Dr. Desire Charles Van Monkhoven, 

 who died on the 25th of September last, 

 just forty-eight years old, was at once dis- 

 tinguished as an astronomer, a chemist, an 

 optician, and a photo-chemist, and was also 

 an active and capable man of business. 

 He was best known by his researches in 

 optical questions bearing on photography, 

 and particularly by his practical applications 

 of them in the Monkhoven solar enlarging 

 apparatus, the Monkhoven tissue for carbon 

 printing, and the Monkhoven gelatine plates, 

 which he invented, and of which he directed 

 the manufacture. He was the author of a 

 general treatise on photography and of pa- 

 pers on his spectral and other researches, 

 contributed to various periodicals. 



On the 22d day of April, and on rainy 

 days afterward, the water in some parts of 

 the city of Lille became unfit for use. M. 

 Geard, investigating, found the cause of the 

 trouble to be the growth of a mucidine of 

 the genus Cremoiryx, which, greedily ab- 

 sorbing iron, produces in the pipes masses 

 of ochreous matter, the putrefaction of 

 which disengages sulphureted hydrogen in 

 considerable abundance. 



A venomous lizard has been presented 

 to the Zoological Gardens of London by Sir 

 John Lubbock. It is called Hthdcrma hor- 

 richim, or horrid warty-skin ; it is from Mexi- 

 co, and is described as about " one foot and 

 a half in length, of a somewhat thickish 

 form, and with a rather short, pointed tail. 

 Except in color its aspect is not prepossess- 

 ing." It is of a pale ochre, or corn-color, 

 coarsely reticulated with black marks. All of 

 its teeth are connected with poison-glands. 



Mr. W. O. Crosby, of Boston, proposes 

 to account for the origin of the seams run- 

 ning in three directions, by which many rocks 

 are cut up into rectangular blocks, as from 

 earthquake-action. Professor H. F. Wal- 

 ling, of Washington, agrees with him. When 

 the papers of these gentlemen were read in 

 the American Association, Professor New- 

 berry, having expressed a sense of obliga- 

 tion to the authors for bringing the subject 

 forward, said that he was inclined to think 

 magnetic currents may have had some part 

 in the production of the joints. Professor 

 Hall called attention to the joints in the 

 clays at Albany, which could not well have 

 been subjected to pressure. 



A correspondent of the London " Daily 

 News " states that some interesting objects 

 have recently been found in Neufchatel 

 which are considered by Swiss archaeologists 

 to throw a new light on the history of the 

 lake-dwellers. Among the objects are a 

 carriage-wheel with an iron rim, iron swords, 

 and many human bones. 



