The fumigation of a large house is merely a repetition, in each room and hall, of the operations already described for a single room. All the rooms should be made tight, and the proper quantities of water and sulfuric acid should be measured and poured into jars placed in each room with the cyanid in bags besides the jars. When all is ready, the operator should _go to the top floor and work downward_ because the gas is lighter than air and tends to rise. PRECAUTIONS The cyanid should be broken up into small pieces not larger than small eggs. This can best be done on a cement or brick pavement. It would be advantageous to wear gloves in order to protect the hands, although the writer has broken many pounds of cyanid without any protection on the hands. Wash the hands thoroughly at frequent intervals in order to remove the cyanid. The operations of the work must be carried out according to directions. The work should be done by a calm, thoughtful and careful person--best by one who has had some experience. Conspicuous notices of what has been done should be placed on the doors, and the doors should be locked so that no one can stray into the rooms. The gas is lighter than air, therefore one should always begin in the rooms at the top of the house and work down. After fumigation is over the contents of the jar should be emptied into the sewer or some other safe place. The jars should be washed thoroughly before they are used again. _It must be remembered that cyanid is a deadly poison_; but it is very efficient against household insects, if carefully used, and is not particularly dangerous when properly handled. LESIONS PRODUCED BY THE BITE OF THE BLACK-FLY While this text was in press there came to hand an important paper presenting a phase of the subject of black fly injury so different from others heretofore given that we deem it expedient to reproduce here the author's summary. The paper was published in _The Journal of Cutaneous Diseases_, for November and December, 1914, under the title of "A Clinical, Pathological and Experimental Study of the Lesions Produced by the Bite of the Black Fly (_Simulium venustum_)," by Dr. John Hinchman Stokes, of the University of Michigan. RESUME AND DISCUSSION OF EXPERIMENTAL FINDINGS The principal positive result of the work has been the experimental reproduction of the lesion produced by the black-fly in characteristic histological detail by the use of preserved flies. The experimental lesions not only reproduced the pathological pictures, but followed a clinical course, which in local symptomatology especially, tallied closely with that of the bite. This the writer interprets as satisfactory evidence that the lesion is not produced by any living infective agent. The experiments performed do not identify the nature of the toxic agent. Tentatively they seem to bring out, however, the following characteristics. 1. The product of alcoholic extraction of flies do not contain the toxic agent.