August 18, 1916] 



SCIENCE 



253 



plating. Beef infusion agar at + 1-5 to be used 

 in making counts. 



Two series of samples from ten dealers were 

 examined. In the first series collected in mild 

 weather, six samples gave total counts of over ten 

 million per gram. In the second series collected 

 during colder weather five samples gave counts of 

 over ten million. Meat from three dealers showed 

 exceedingly high counts in both series, indicating 

 that bad methods were followed. 



The chief cause for high counts is to be found 

 in the practise of utilizing scrap meat or meat of 

 inferior quality which is often collected and held 

 for some time before being ground up for sale. 



Attention is called to the value of bacteriolog- 

 ical analyses as a means of determining the meth- 

 ods used by dealers and to the importance of this 

 test being more generally resorted to in connection 

 with chopped meats for the purpose of establish- 

 ing proper standards and securing an efficient 

 sanitary control. 



Cleaning Silver by Contact with Aluminium in Al- 

 kaline Solution: H. L. Lang and C. F. Walton, 

 Jr. 



This paper is a preliminary report of results ob- 

 tained in cleaning silver under household condi- 

 tions by the electrolytic method. Sodium car- 

 bonate was found to be slightly more efficient than 

 the bicarbonate as the electrolyte of the method, 

 one teaspoonful of each washing soda and table 

 salt to the quart of water proving the most eco- 

 nomical concentration. The best results were ob- 

 tained when the cleaning solution was kept at the 

 boiling temperature during the cleaning, and 

 aluminium proved more efficient than zinc as the 

 active metal in contact with the silver. 



The principal advantage of the electrolytic 

 method, as compared with cleaning by an abrasive 

 polish, is that it saves labor. In addition it is 

 convenient and clean, and removes the tarnish 

 from both sterling and plated silverware without 

 appreciable loss of the metal. 



Iron Bust Stains and Their Removal: New Meth- 

 ods: Harold L. Lang and Anna H. Whittel- 

 sey. 



In an experimental study of the removal of 

 stains from textiles several new or little-known 

 reagents were found successful for the treatment 

 of iron rust spots. A 15 per cent, solution of 

 titanium trichloride, TiCl 3 , applied cold to the 

 stain was found to be very efficient, although an 

 expensive reagent. Iron rust stains could also be 

 removed by boiling for several minutes in solu- 

 tions of potassium acid tartrate (cream of tartar), 



tartaric acid or citric acid, or in an infusion of 

 the stalks, leaves or fruit of certain plants which 

 contain oxalic or other acids. Among these plants 

 are rhubarb, the begonia (a rather common house 

 plant), the pineapple, and the grapefruit. These 

 reagents have the advantage that they may be 

 readily obtained and are less liable to injure the 

 fabric or its color than are hydrochloric and oxalic 

 acids, whose efficiency are well known. 

 Solutions of Lead and Antimony from Enameled 

 Cooking Utensils: Elizabeth W. Miller. 

 Fifteen different makes of enameled dishes 

 were boiled with 4 per cent, acetic acid and the 

 solution tested for lead and antimony. Slightly 

 less than 2 mg. of lead per liter were dissolved 

 from the saucepan of standard make. Three 

 others of the same kind gave mere traces. 



Antimony was extracted by acetic acid in con- 

 siderable amount from one cheap gray dish. 

 Grape juice, cider and cranberry pulp, milk and 

 spinach were cooked in dishes of this same make. 

 All these foods contained antimony in amounts 

 ranging from 2.3 mg. in 200 c.e. of milk to 14 mg. 

 in 200 c.c. of cranberry pulp. 



History and Present Methods of Fluorspar Pro- 

 duction in Illinois: Carl C. Luedeking. 

 The author after giving a short history of the 

 mining and milling methods of fluorspar in Pope 

 and Hardin counties, Illinois, enters into the de- 

 tails of present-day status in this industry. It ap- 

 pears that four fifths of the fluorspar of the 

 United States comes from the Fairview and Eosi 

 Clare mines of Hardin County, Illinois. In 1914 

 these mines have produced 70,000 of the 78,000 

 tons of fluorspar used in this country. In 1915 

 the production increased to 115,000 tons. The 

 fluorspar is used chiefly in the basic open hearth 

 steel furnaces and for enameling. 

 The Chemistry and Technology of Glass: Alex- 

 ander Silverman. 



After a brief introduction on the history of 

 glass making, followed by a statement concerning 

 raw materials, their functions and uses, the tech- 

 nology of glass making was illustrated by about 

 sixty lantern slides. A discussion of coloring and 

 decolorizing agents followed and parallels were 

 shown between aqueous and vitreous solutions of 

 gold, compounds of uranium, copper, cobalt, alu- 

 minium, chromium, etc. Specimens of glass and 

 related aqueous solutions were exhibited to illus- 

 trate the points discussed. Data on the treatment 

 of glass included recent developments in etching, 

 polishing and silvering processes. The importance 

 of careful and comprehensive research in this 



