Cold And Magnetism

■ A recent iuvestigation, cöndncted in the pbysicftl laboratory of Harvard Universit.v, bas lead to the discovery of the mnarkal!.faet that intense cold can deprive magnetized steel bars of ncarly all the the ïuagnetism that may have been iiuparted to thent. The intense cold was produced by eolid cnrbouic acid. This tact has an important hearing upon observations of the jnagnetic couditioa of the earth in high -latitudes; for vrhat appear to be daily aud yearly changes in the earth's inagnctism ■may bé duo in large part to conditious of temperaturc, which affect the niagncts uscdin the observatious. It also must bc cooclndcd that the molecular condition oi stel is changed by great cold, 1