 Cade found that in the guinea pigs injected with lithium carbonate solution, as a control solution, the guinea pigs were more restful.His use of careful controls in his experiments revealed that the lithium ion had a calming effect by itself, but even this finding may have been caused by the toxic effects of an excessive dose of lithium.After ingesting lithium himself to ensure its safety in humans, Cade began a small-scale trial of lithium citrate and/or lithium carbonate on some of his patients diagnosed with mania, dementia præcox or melancholia, with outstanding results.