310 Notes and Memoranda. 



refrangibility. These exhibited lines independent of the electrodes, and therefore 

 referable to the air." 



Immense Casting-. — A mass of iron for a pile hammer has just been cast at 

 the Usines de l'Horme, near St. Chamond, that weighs 38,000 kilogrammes ; 

 1 kilogramme is equal to 2'670 lbs. avoirdupois. It will be transported to Bive-de- 

 Gier, on a truck drawn by eighty-eight oxen, harnessed in fours, and led by twenty- 

 two waggoners. — Cosmos. 



Variable Nebula. — M. D'Arrest announces that two other nebula? in Taurus, 

 only eight or nine degrees from that of Mr. Hind, exhibit indubitable variability. 

 The first is that discovered by M. Tempel at Venice on the 19th October, 1859. 

 It had 3h. 37m. 7s. E. A., and 23° 23' D. This nebula of the Pleiades was described 

 by M. Tempel as easily visible. In December, 1860, MM. Peters and Pope saw it 

 with difficulty through the equatorial at Altona. In August, 1862, M. D'Arrest 

 could no longer see it with the powerful telescope at Copenhagen. The second of 

 the nebula? in question is one of those observed at Bonn, and afterwards on the 

 5th February, 1859, by Mr. Tuttle, at Cambridge. Now it is almost invisible. 

 These three nebulse are the only ones, according to M. D'Arrest, whose variability 

 is beyond doubt. — Cosmos. 



New Gunpowder. — M. Schultz, a Prussian captain of artillery, has invented 

 a new powder, used for the first time at the Frankfort rifle meeting. It is said 

 to be cheaper, lighter, and more effective than the common sort, and to leave the 

 barrel quite clean after thirty discharges. It is in brownish-yellow grains, like 

 wood saw-dust. Its composition is not stated. The Austrians are reported to be 

 successful in the employment of gun cotton for artillery. 



Closing Fruit Jabs. — The Homestead recommends instead of corks, tying the 

 mouths of the jars, while still hot, with strips of cloth, saturated with equal parts 

 of beeswax, resin, and tallow. The superfluous cloth should be cut off, and then 

 dipped in melted wax, with half its weight of tallow. 



An Amalgam oe Cadmium. — As most amalgams are brittle, it is remarkable, 

 as Dr. B. Wood mentions in Chemical News, that equal parts of cadmium and 

 mercury should form a tough and highly malleable composition. 



Engelmann on Infusoria. — Dr. Arlidge publishes, in Annals of Natural 

 History, an abstract of researches in infusoria, by T. W. Engelmann. This 

 observer confirms Miiller's discovery of spermatozoa in Paramecium aurelia, and 

 says they are not, as usually represented, thin rods equally pointed at both extremi- 

 ties, but have a bulky anterior, and a thinner posterior extremity of greater 

 transparency. Their maximum length is 0008 of a millimetre. "The embry- 

 onic development observed by Stein in Stylonicliia mytilus, also fell under his 

 notice. In 1859 he found specimens containing embryonic corpuscules ; but it 

 was not till the autumn of 1861 that he met with examples which illustrated a 

 further stage in their history. These latter were individuals of medium size, and 

 mostly contained but one large embryonic globule, placed between the two nuclei, 

 close behind the angle of the anal aperture. Placed over it, on the central 

 aspect of the animal, there always existed an elliptic or rounded opening, of 

 variable size, which was the outlet for the escape of the mature ovum. On one 

 occasion only was an elongated and rounded dorsal aperture found, in addition to 

 the abdominal foramen just named, and serving like it for the escape of the 

 embryos, the act of birth was several times witnessed ; sometimes the embryonic 

 globules escaped as such, at others they developed tentacles, and assumed the 

 acinetiform figure usually described." He does not know the subsequent history 

 of the embryos, but does not believe in their immediate transition to the ordinary 

 form of Stylonichia, and is disposed to accept Stein's view of an alternation of 

 generations. He rejects Balbiani's doctrine that the acinetiform beings seen to 

 emerge from the interior of various infusoria are parasites. Many other 

 interesting particulars will be found in Dr. Arlidge's notes. 



A Microscopic Vertebrata. — Dr. Wallich publishes, in Annals of Natural 

 History^ a drawing of the jaw of ajninute animal, found in mud dredged^up by 



