A D.C. Superior Court judge yesterday found Lewis A. Dobson, 23, guilty of second-degree murder in the death of a 3-year-old child who was found beaten in an apartment Dobson shared with the child's mother.

Judge Alfred Burka, who presided at the nonjury trial, described as "depressing" testimony from a city deptuty medical examiner who said the child, Raymond Leon Bellinger, apparently "had been (physically) abused for some time" before his death in November 1976.

In closing argument yesterday, Assistant U.S. Attorney Alexia Morrison recalled testimony that the child had suffered a broken leg while in Dobson's care in September 1976. A month later, Morrison said, Raynard's foot was severely burned by hot water after Dobson had volunteered to give the child a bath.

On Nov, 10, 1976, the child's mother, Myra Teeter, had left Raynard with Dobson while she took another son, Devon, to a hospital for treatment after he fell off acouch in the apartment Teetar shared with Dobson at 1111 D St. NE, Morrison told Burka.

Later that day, Teeter received word at the hospital that Raynard was dead, Morrison said. Based on the testimony of deputy medical examiner William Brownless, Judge Burka said he found that death occurred after the child was stomped on the abdomen witn such force that the blow left the imprint of a heel on the child's body.

Defense attorney Steffen W.Graae argued that the "fatal weakness" in the government's case was the fact that there were no witnesses who could place Dobson in the D Street apartment at the time Raynard was beaten. No witnesses were presented in Dobson's defense.

Graae contended that Raynard could have suffered the broken leg while he and Dobson were "wrestling." The burned foot resulted after hot water from a shower dripped onto the child's foot, Graae said.

Dobson was arrested two days after Raynard's death in Columbus, Ohio, where he said he had gone to visit his sister.

Burka scheduled sentencing for June 13. In April, Burka sentenced Dobson to serve 25 years to life in prison after a Superior Court jury convicted him of first-degree murder in a fatal shooting that occurred the September before Raynard Belinger's death.