Dimiti Mandeevu (Dmitri Mendeleev) yafulumya omweso gw'endagakintu ogwasooka mu 1869. Yalaga nti singa endagakintu zisengekebwa okusinziira ku buzito bw'akaziba (atomic weight), kivaamu omusengeko (pattern) nga ebinnyonnyozo by'endagakintu bidding’ana mu bugalamivu (periodically).