It is now about four years since Drs. Bruce and Macphail first published the results of their treatment of cases of insanity by thyroid, and since then the new drug has been used very extensively in the Royal Edinburgh Asylum. Dr. Bruce has published the results of his further experience there, and though they are not quite so encouraging as those first carried out at Derby they have furnished several remarkable cures, and have shown conclusively that in thyroid we have a decided addition to our means of treatment.