Show valuable compound discovered DiK CWIll crystalline ue selenium la in which light produces produce w t remarkable remar bablo a les hig ot of electrical resistance promos lame to be not at the only sub subsume some we BO affect affected ad 1 in th the a experiments ot of the united states bu bil reau ream of to determine pro pre daely casely the properties of 0 mets riola ml such each amp compounds de fix as J at to silver sulphide bermit hm its ite and showed smas change in electro c cal conductivity with iab var aarink mg light fight in the same banie way na as tho the element sel selenium cism |