110 YEAR-BOOK OF FACTS. 



into which the other end of the thrend is inserted. By means of this 

 apparatus M. Persoz has heen enabled to make experiments on the 

 tenacity of various silks, the results of which he has communicated 

 to the Society Imperiale d'Acclimatation. Thus, the threads tested 

 being all of the length of half a metre, M. Persoz shows that 

 the tenacity of the Calcutta cocoon is represented by 5 '3, that 

 of Teneriffe 5 '2, while those from Avignon and Prussia were 12 and 

 12 - 9 respectively ; that of Neuilly marked 8. The elasticity of these 

 sorts per metre was respectively 9 '9, 12"8, 14'4, 13 - 4, and 12*9. The 

 following- general conclusions derived from these experiments are 

 interesting: — 1. The male cocoon yields a finer and more tenacious 

 silk than the female one. 2. The same species reared on different 

 soil and in different climates does not yield threads of the same 

 tenacity. The latter fact, M. Persoz thinks, should induce the 

 Society d'Acclimatation to undertake experiments for the sake of 

 determining with precision the effects which soil and climate, as well 

 as the kind of food, produce on the silk worm. — Galignam 8 Messenger. 



BITUMENIZED PAPER PIPES. 



Experiments have been made for testing a new kind of Pipe or Tube 

 made of Paper and Bitumen, and intended to serve many of the pur- 

 poses for which metal pipes and tubes have hitherto been employed. 

 The ingenious idea of hardening paper by means of an admixture of 

 bitumen under the influence of hydraulic pressure, so as to convert 

 it into a substitute for iron, is due to M. Jaloureau, of Paris, who 

 was present, and explained his process. The world has already 

 become familiar with the universal utility and value of papier milche", 

 with the beautiful application of paper as a substitute, equal in 

 appearance to stone or marble, for moulding, architectural castings, 

 busts, and statues ; it has also heard recently that the Chinese con- 

 structed their cannon of prepared paper lined with copper — that an 

 eccentric character at Norwood has built himself a house of paper, 

 and that our American friends have invented a veritable paper brick 

 — but nothing probably has lately come before the British public in 

 tlir way of paper so curious, and yet so commercially practicable and 

 useful, as these bituminous paper pipes. The process of fabrication 

 was fully explained, and the testing experiments, which were con- 

 ducted under the great clock-tower at the Houses of Parliament, 

 proved, to the surprise and satisfaction of all present, that the mate- 

 rial, while it possessed all the tenacity of iron, with one-half its 

 ■pacific gravity, had double the strength of stoneware tubes, without, 

 m o r eo v e r, \<< ing liable to breakage, as in the case of other materia], 

 and which frequently causes a loss to the conductor of some 20 OT 

 26 prcent. on tho supply. In order to test their strength, two "f 

 these bituminous paper pipes of 6 inch bore and .'. inch thick, were 

 ■objected to bydraolio power, and they sustained, without breaking 



or hurstiiiLC, the eiior us pressure of 220 lb. to the square inch, or 



equh alent to 500 Coot head of water, being double the actual pressure 

 that the present London water-pipes of Iron have to bear. In 

 another exp e rim ent, to test the transverse strength of the material 



