Bearing upon the subject of smoke prevention it is worth recalling that in 1890 the Society of German Engineers instituted a prize essay competition, offering two prizes, one for the best essay on steam boiler firing and the other for the best one on the household use of coal. It was intended that the essays should be critical reviews of what had been done in the past in the way of burning coal economically and with a minimum of smoke production, and should discuss the results obtained. The time limit for the essay on the first subject expired on Dec. 31, 1892, but none of the six essays which had been received were deemed worthy of the prize. Considering the importance of the subject, a new competition is to be instituted, and the money value of the prize to be offered is to be increased to 5,000 marks, or about $1,250. An extra allowance of $250 is to be made for expenses to be incurred in the preparation of drawings. Particulars of the competition can, no doubt, be obtained by addressing the Vcrein deusceher Ingenieure, Berlin.