Intelligence and Miscellaneous Articles, 459 



tartaric acid entirely destroys it in ten or twelve minutes. If the 

 solution contains only one part of tartaric acid in 1000 water, at the 

 end of three minutes the circulation is very much retarded, but after 

 five minutes it is accelerated ; at the end of three quarters of an hour 

 it is again retarded, and after one hour's immersion it altogether 

 ceases. 



The circulation is immediately destroyed by water holding ;^th 

 of its weight of marine salts in solution ; the liquid makes a disorderly 

 movement, the range of green globules are dissociated and become 

 confusedly dispersed. 



In a solution containing g^^th of its weight of marine salt the cir- 

 culation is stopped at the end of four minutes, and slight convulsive 

 movements are manifested ; after eight minutes the circulation is re- 

 established and accelerates gradually, continues for eight days and 

 then definitively ceases. A solution of one part of a watery extract of 

 opium in 144 parts of water destroys the circulation in six minutes. 

 In a solution of one part in 288 parts of water the circulation is sus- 

 pended at the end of eight minutes, but ceasing for ten minutes, it 

 begins again and becomes more rapid than it is naturally ; it lasts thus 

 during eighteen hours, then diminishes its quickness, and after twenty 

 two hours it ceases altogether. Water containing -^Q^h. of its volume 

 of alcohol, of 36 degrees strength, considerably diminishes the quick- 

 ness of its circulation at the end of five minutes ; then after ten 

 minutes the movement recommences, accelerated by the vital reaction, 

 and becomes very rapid ; it ceases altogether at the end of 42 hours, 

 after gradually diminishing in quickness. — L'Institut, No. 223, Janu- 

 ary 1838. 



OXALO-NITRATE OF LEAD. 



M. Dujardin describes a new double salt, formed of two acids united 

 to one base, which he has obtained, and calls an oxalo- nitrate of lead. 

 It may be formed by dissolving, by the aid of heat, oxalate of lead 

 in weak nitric acid ; the liquid on cooling deposits brilliant white 

 crystals in the form of rhomboidal plates, which appear to be de- 

 rived from the right prism. It remains unchanged upon exposure 

 to the air, is decomposed by heat, which drives off two atoms of 

 water of crystallization, and disengages afterwards a mixture of ni- 

 trous and carbonic acids in red fumes. Water decomposes it, dissolving 

 the nitrate of lead, and leaving the oxalate in the state of a white 

 powder ; but if nitric acid is added and slightly heated the oxalate 

 is redissolved and the double salt reproduced. This salt is composed 

 of one atom of nitrate of lead, one atom of oxalate of lead, and two 

 atoms of water. 



This is the only double salt of this kind which has been obtained ; 

 the other insoluble oxalates do not form combinations with the 

 corresponding nitrates. Oxalate of manganese is even entirely 

 decomposed by warm nitric acid, whilst oxalate of cerium simply 

 dissolves and crystallizes on cooling ; oxalate of copper is neither dis- 

 solved or decomposed. 



M. Dujardin also remarks that the double salts described in che- 

 mical treatises, as composed of phosphate and nitrate of lead, cannot 



