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(Continued from page 60.) 



Nitroglycerine was found so difficult to handle that five years after- 

 wards Noble invented dynamite, which is simply a sand soaked with 

 nitroglycerine. Other absorbents for it have also been used, and the giant 

 powder so much used in western mines is a mixtureofcommon gunpowder 

 and nitroglycerine. The new blasting gelatine is simply nitroglycerine in 

 which 7 or 8 per cent, of gun cotton has been dissolved. Lithofracteur, 

 dualine, colonia powder, fulminatine, sebastine, serranine, rackrock, 

 atlas powder, vulcan powder, neptune powder, forcite, are all mixtures 

 containing nitroglycerine. Hellhoffite, carbonite, roburite and kinetite 

 have nitrobenzol for the explosive constituent. Mellinite consists 

 essentially of picric acid. As for smokeless powders their name is legion 

 and it would be useless to go into their composition. One of them, 

 however, may be mentioned, namely cordite said to have been invented 

 by Sir Frederick Abel and Professor Dewar. It is said to consist of nitro- 

 glycerine and gun cotton or some other nitrocellulose, and to have been 

 adopted by the British Government for the army and navy. 



(Experiments were here introduced ; the burning of gun cotton and 

 of nitrocellulose.) 



I have already indicated to you the percentage composition of the 

 albumen of eggs, the casein of milk, and the fibrin of blood, and I 

 might go on and characterise many other of the animal albumenoids 

 which have been separated by chemists. This is, however, unnecessary 

 for our present purpose and besides there have been detected in the 

 examination of the animal fluids and tissues other albumenoids very 

 difficult to classify under the headings which have so far been adopted 

 by chemical physiologists. In fact ; products seem to have been dis- 

 covered which indicate the existence of transitions or gradations betwixt 

 those albumenoids which have already been accepted as pretty well 

 defined compounds. 



There exists, however, another set of albumenoids in the bodies of 

 animals which it is impossible in a lecture on Nitrogen to pass over 

 without notice. Beilstein calls them the Protein substances of the 

 connective tissue. In English they are sometimes called the fibrous 

 albumenoids and are a very curious class of substances. To it belong 

 hair, wool, glue, etc., which in spite of their different characters are 

 similar in composition. 



