CHAPTER XI.

TESTING GLUE AND GELATINE.

Determination of moisture; Determination of ash; Determination of acidity 205

Determination of glutin; Bisler-Beumat’s method 206

Analysis of samples of American glue by S. Dana Hayes; Deduction of the quality of glue from indirect properties 207

Lipowitz’s method of testing the strength of a glue, described and illustrated 208

Results obtained by comparative experiments 209

Facts shown by the results 210

Weidenbusch’s method of testing glue 211

Preparation of the plaster of Paris stick and of the glue solution used in this test 212

Apparatus for testing the strength of the plaster of Paris sticks, described and illustrated; Test adopted by the “Artillerie Werkstätte” at Spandau 213

Determination of adulterations 214

Kissling’s results in testing a large number of samples of glue 215

Practical tests of glue 216