VI. FORESTRY.--Succession of Forest Growths.--A valuable paper on forestry, treating of the evils done by man and a plea for the necessity of intelligent treatment of our woods. 11362 VII. HYGIENE AND MEDICINE.--Acetic Acid as a Disinfectant.--Use of acetic acid in septic medical cases as a substitute for carbolic acid and bichloride of mercury. 11365 Counter-Irritation in Whooping Cough.--By G.F. INGLOTT, M.D.--Application of irritants to the skin for curing the paroxysms of whooping cough. 11365 On the Health Value to Man of the So-called Divinely Beneficent Gift, Tobacco.--By J.M.W. KITCHEN, M.D.--The evils to man and to the soil.--A formidable series of accusations well expressed. 11365 Water as a Therapeutical Agent.--By F.C. ROBINSON, M.D.--An interesting resume of different applications of water in therapeutics.--Suggestions of use for all households. 11364 VIII. MILITARY ENGINEERING.--Gibraltar.--A history of this important strategic position and of the different sieges the fortress has undergone. 11352 Gibraltar and Neighborhood.--A consular report on the statistics of the famous military station. 11352 The Defense of Gibraltar--Experimental Naval and Military Operations.--Interesting series of operations recently carried out under the shadow of the historic rock.--1 illustration. 11352 IX. NAVAL ENGINEERING.--Clark's Gyroscopic Torpedoes.--A recent torpedo, in which all the possible parts are made to rotate.--2 illustrations. 11353 The First Steamboat on the Seine.--The Marquis de Jouffroy's steamer of 1816.--1 illustration. 11353 The Franz Josef I., New War Ship.--Details of the dimensions of the new Austrian ship.--Her armament, speed, armor, etc. 11353 X. PHOTOGRAPHY.--Orthochromatic Photography.--By OSCAR O. LITZKOW.--The last developments in this interesting branch of photographic art, with formulae. 11360 Platinotype Printing.--A description of the most advanced method of conducting the platinum print process. 11360 XI. PHYSICS.--Iridescent Crystals.--By LORD RAYLEIGH.--An abstract of a lecture by the distinguished physicist, detailing some interesting experiments applicable to the colored reflection observed in crystals of chloride of potash.--1 illustration. 11366