This relationship is additionally emphasized by referring to the memoranda concerning certain overcrowded houses, in the midst of the rat plague district, where multiple human cases occurred. (See memoranda in re 1226 Calle Juan Luna and 1364 Calle Sande.) [Illustration: CLEANING AND RAT PROOFING IN BASEMENT OF 1226 CALLE JUAN LUNA IN WHICH TWO CASES OF PLAGUE OCCURRED. RAT CADAVERS FOUND UNDER BROKEN FLOORS (MANILA PLAGUE CAMPAIGN)] The human cases in April were 5 in number, all originating in the same house, and the May cases numbered 4, two of which occurred in the same house. It may be explained, in passing, that two cases of human plague, discovered in Malolos, 25 miles from Manila, on March 23 and March 26, respectively, were definitely traced to the same house in Manila, number 12 Calle Aguila, Tondo, both patients having lived in the basement of this house until within 48 hours of the development of the disease. These persons were unrelated and were two of a large number of people who lived in a tenement at this address. Both patients were detected, while still alive, in Malolos, where they were living in different and widely separated houses. One of the patients died in Malolos but the other one was brought to Manila by train and died at San Lazaro Hospital. Fortunately no infection was transferred to Malolos by these two persons. In this connection it is interesting to note that no other cases have been reported from outside of Manila, except the small outbreak in Iloilo in the southern islands, where the antiplague work was successfully directed by Dr. Carroll Fox. Concerning this outbreak, Dr. Heiser, then Director of Health for the Philippines, writes as follows (_Philippine Journal of Science_, February, 1914): PLAGUE IN ILOILO.--In Iloilo, a case suspicious of plague was reported on July 5, 1912, and this diagnosis was subsequently confirmed by the laboratory. It occurred in the person of a Chinaman who was reported to have come from Bais, Oriental Negros, but later investigation showed that he had been a resident of Iloilo at least since February, 1912. The next case was reported August 18, and the last case, September 17, 1912. There was a total of 9 cases. All of the cases were confined to two houses. During July, August, September, and October, 1146 rats were caught in the vicinity of the houses in which the human cases had occurred, along the water front, and in the places which were regarded as suspicious, but in not a single instance was an infected rat found. DIRECTED TO TAKE CHARGE OF PLAGUE SUPPRESSIVE MEASURES.--Upon my arrival in Manila from the United States, on October 23, 1912, I received orders from the Director of Health to take charge of all plague suppressive measures in Manila and I remained in charge of this work continuously until July 11, 1914.