210 



SCIENCE, 



[Vol. YI., No. 136. 



have a good knowledge of the principles of chem- 

 istry. Sanitary inspectors should be familiar with 

 certain chemical tests which would enable them 

 to make preliminary examinations, and to determine 

 how far the aid of the chemist is necessary. There 

 is room in the community for a class of persons 

 knowing a little engineering, a little chemistry, a lit- 

 tle biology, and a little of other things, an occupa- 

 tion legitimate and honorable, but one which does 

 not justify our calling a person so posted a sanitary 

 engineer, or a chemist. 



PROCEEDINGS OF THE SECTION OF 

 CHEMISTRY. 



The meeting of the chemical section had an 

 unusually large attendance ; and Ann Arbor, 

 not having very many attractions to withdraw 

 the attention of members, allowed all chemists 

 in attendance to be present. The total number 

 of papers presented was small, — in all only 

 seventeen. Of these one was not chemical, 

 one was ever}^ thing, one organic, one applied, 

 two mathematical, two pharmaceutical, three 

 theoretical, and six analytical. The meeting, 

 while not brilliant, was respectable, and was 

 remarkable chiefly for the absence of the older 

 and more renowned chemists of the countr3\ 

 It would certainlj' be an advantage if these 

 would more generally endeavor to attend the 

 meetings of the association, and encourage the 

 younger members by their counsel. Following 

 is a brief synopsis of the more important 

 papers presented : — 



Prof. A. B. Prescott gave results of experiments 

 made under bis direction, fixing the limits of recov- 

 ery of certain poisons when mixed with organic mat- 

 ter, such as meat and bread. 



Prof. W. A. Noyes read a paper on para-nitro- 

 benzoic sulphunide. This body belongs to the class 

 of sulphunides, the first representative of which was 

 discovered by Fablberg. The new substance is 

 remarkable, in that it retains the imide grouping 

 peculiar to the sulphunides in its salts. This nitro- 

 sulphunide is intensely bitter, while benzoic sulphu- 

 nide is probably the sweetest substance known. 



Dr. H. W. Wiley presented a method of estimating 

 lactic and acetic acids in sour milk or koumiss. The 

 caseine is precipitated by adding an equal volume of 

 strong alcohol to the milk. After filtering, the acid 

 is determined in the filtrate, using phenyl-phthalein 

 as indicator. The same author spoke of the composi- 

 tion of koumiss made from cow's milk. The analyses 

 show a lower percentage of alcohol and lactic acid, 

 and a higher one of milk-sugar and fat, than are found 

 in European samples, whether made from cow or 

 mare's milk. The adulteration of honey was also 

 discussed by Dr. Wiley. The honeys of commerce 

 are found to be largely adulterated. The substances 



most used for this purpose are, starch-sugar sirup 

 (glucose), cane-sugar, and inverted cane-sugar. Ke- 

 sults of numerous analyses made at the department 

 of agriculture were given, and a comparison of Amer- 

 ican honeys made with those of Europe. 



Messrs. H. W. Wiley and F. Y. Broadbent described 

 a new method of estimating water in glucose, honeys, 

 etc. Samples are dissolved in alcohol mixed with a 

 weighed portion of sand, and dried. After cooling 

 to 70° C, they are saturated with absolute alcohol, and 

 dried again to constant weight. 



Messrs. E. H. Cowles, A. H. Cowles, and C. F. 

 Mabery, presented an important and interesting paper 

 on a new electric furnace, and aluminum alloys made 

 in it. The furnace is of fire-clay. The mass to be 

 acted on is mixed intimately with finely-powdered 

 gas-carbon, and is placed in the break between the 

 two electrodes, which are inserted in the two ends of 

 the furnace, and connected with a powerful dynamo- 

 electric machine. The mass to be reduced is sur- 

 rounded with coarsely pulverized charcoal, to prevent 

 the heat produced from attacking the fire-clay fur- 

 nace. The temperature of the furnace is high enough 

 to produce an alloy of copper and aluminum, when 

 the ahiminum is present in the state of oxide, or even 

 of silicate. The aluminum alloys produced by this 

 method cost much less than when made in the old 

 way. The five per cent aluminum alloy is a close ap- 

 proximation in color to 18 carat gold, and does not 

 readily tarnish. Its tensile strength, in the form of 

 castings, is equivalent to a strain of 68,000 lbs. to the 

 square inch. An alloy containing two or three per cent 

 aluminum is stronger than brass, possesses great 

 permanency of color, and would make an excellent 

 substitute for that metal. The effect of silicon in 

 the small portions, upon copper, is to greatly increase 

 its tensile strength; and copper and silicon alloys are 

 made easily in the furnace. When more than five per 

 cent of silicon is present, the product is extremely 

 brittle. Alloys of copper and boron have also been 

 made. Boron seems to act upon copper as carbon 

 does on iron. A small percentage of boron in copper 

 increases its tensile strength to 50,000 or 60,000 lbs. 

 per square inch, without diminishing to any great 

 extent its conductivity. Aluminum seems to increase 

 very considerably the strength of metals with which 

 it is alloyed. An alloy of copper, nickel, and zinc, 

 containing a small percentage of aluminum, has been 

 named 'Hercules metal,' and withstood a strain of 

 105,000 lbs. to the square inch. The strength of com- 

 mon brass is doubled by the addition of two to three 

 per cent of aluminum. Alloys of aluminum and iron 

 are obtained, without difficulty, in the furnace. One 

 product was analyzed containing forty per cent of 

 aluminum. 



A chemical study of Yucca angustifolia was pre- 

 sented by Miss Helen C. D. Abbott. Besides many 

 of the usual constituents found in plants, the follow- 

 ing were detected : manganese in the ash, four fixed 

 oils, a new resin which it is proposed to name yuccal, 

 another new resin which it is proposed to name 

 pyrophaeal, a red crystalline coloring matter, a new 

 gum, four crystalline compounds, and saponin. In 



