STIRRING RODS 161

REPORT OF THE SIXTIETH MEETING OF THE EASTERN AS-SOCIATION OF PHYSIOS TEACHERS.

This meeting was held Saturday, December 2, at the Howard Univer-sity Observatory. It was called to order by President Griswold, whointroduced Professor Pickering, director of the observatory, who gave amost interesting talk on what had been and what was being done, especi-ally in the direction of photometry of the stars at this observatory.A tour of inspection of the observatory grounds and buildings was

participated in by all the members present. This part of the program wasparticularly enjoyable and interesting as the inner working of the depart-ment was explained.Valuable reports from the standing committees on: New Apparatus,

Magazine Literature and Current Events in Physics were presented.It is hoped that the committee on New Apparatus will prepare its reportfor publication in SCHOOL SCI^NC^ AND MATHEMATICS.

Several new members were elected to the Association.Dr. Arthur Amadon of Boston delivered a splendid address on "The

Uses of the Spectacle Lenses for the Correction of Refractive and OtherErrors of the Eyes and the Instruments Used for Determining SuchErrors." This was ^most interesting and helpful talk. It is hoped thatthe paper will be published in this Journal.

Professor Harry W. Morse of Harvard University then spoke on thesubject of "The Compound Microscope." He called attention to some ofthe newer adaptations of the Compound Microscope, explaining what re-markable advances had been made in the construction and uses of thisinstrument within the last ten years.After this address the members were given the special privilege of

being permitted to visit the renowned Clock Lens Works. Many interest-ing points of especial importance to physics teachers were here madeknown.At the evening session, held at the Boston City Club, Vice-President

Fred H. Cowan gave the annual address. He called attention to thedifferent phases of work in which the Association has engaged and alsoto the valuable work which if has already done.Following this address a discussion of the topic: "The Scope and

Content of a Physics Course in Secondary Schools" was dealt with. Onthe whole this meeting was one of the most helpful ever held by theAssociation. C. H. S.

STIRRING RODS.By NICHOI/AS KNIGHT,

Cornell College.Instead of the ordinary solid rod we have used for years in our labora-

tory glass tubing three sixteenths or four sixteenths inch in diameter.These tubes are cut into convenient lengths and the ends fused togetherin the Bunsen burner or the blast lamp. These are lighter and strongerthan the solid rod for the same reason that the cones are hollow. Andthey are^ less liable to break the beaker glass. Continued and vigorousstirring is desirable in many experiments in general chemistry. In quali-tative and quantitative analysis the reactions often take place only afterconsiderable stirring. "Spare the rod and spoil the analysis" is a veryproper maxim for the analytical laboratory. The hollow rod is an ob-vious advantage and it will prolong the life of many a beaker glass andavoid beginning over again an experiment or an analysis.