The book Foams: Theory and Industrial Applications, written by the undersigned and three collaborators and published in 1953, is still the only monograph on liquid foam in the English language. Naturally the science of foams had advanced in the intervening years so that a practically new book had to be prepared to give justice to the present state of our know­ ledge. This monograph has only one author and does not deal with solid foams, fire-fighting foams, and flotation, on which information is available elsewhere. The other applications of foam and its fundamental properties are reviewed at length and, whenever possible, attempts are made to reach the truth through a maze of conflicting evidence. February 1973 J. J. BIKERMAN Contents page Preface . v 1. General. Foam Films (Sections 1-22) 1 Foam Films 5 References 30 2. Formation and Structure (Sections 23-42) 33 Dispersion Methods 33 Condensation Methods 51 Foam Structure 59 References 62 3. Measurement of Foaminess (Sections 43-62) 65 Films and Bubbles 66 Foams. 76 References 94 4. Results of Foaminess Measurements (Sections 63-84) . 98 Poorly Foaming Liquids . 98 Strongly Foaming Liquids 108 Other Systems 132 References 140 5. Three-phase Foams (Sections 85-90) 149 References 157 6. Foam Drainage (Sections 91-106) 159 Experimental Data . 173 References 181 7. Mechanical Properties of Foams (Sections 107-122) 184 References 211 8. Optical Properties of Foams (Sections 123 -127) . 214 References 222 vii viii Contents 9.