192 Portable Gas Light Companies. 
87. Annual return of migrating birds to the sam€é spot.— 
The late Dr. Jenner, in a curious paper on the migration of 
birds, published since his deata in the Phtl. Trans. for 1824, 
mentions the following curious experiment.‘ Ata farm-house 
in the neighbourhood, I procured several swifts, and by taking 
off two claws from the foot of twelve, | fixed upon them an in- 
delible mark. The year following, their nesting places were 
examined in an evening, when they had retired to roost, and 
there I found several of the marked birds. The second and 
third year, a similar search was made, and did not fail to pro- 
uce some of those that were marked. I now ceased to 
make an annual search ; but at the expiration of seven years, 
a cat was seen to bring a bird into the. farmers kitchen, and 
this also proved to be one of those marked for the experi- 
ment.—Jbid. m : 
38. Red Snow.—-The red snow which Mr. Bauer has so ad- 
mirably figured and described under the name of Uredo niva- 
lis, Dr. Hooker in the Botanical appendix, which will soon 
appear, to Capt. Parry’s second voyage, has been disposed to 
look upon as belonging to the genus Palmella of Eyngbis, 
Ina letter which we have just received from Professor Agardh, 
of Lund, the esteemed author of so many publications on by- 
drophytology, that gentleman thus expresses himself :—“A 
very curious fact, I will mention to you. I have ascertained the 
singular circumstance that the red snow is an Alga, which [ 
call Rotococeus nivalis, and that it is found not only upon all 
Alps in the Spring, but also on limestone in Sweden, during 
the summer. It had been observed by Linnzus, and then 
described asa lichen by Baron Mangel. Having had the op- 
-—portunity of examining both the [tehen and the red snow from 
the arctic expedition, | find them to be absolutely the same. 
y memoir on this singular subject will be published in the 
Act. Acad. Nature Cauriosorum in Germany,” —/éid. 
39. Portable Gas Light Companies.—Our readers will 
have much satisfaction in learning, that the Portable Gas Com- 
pany of London is succeeding beyond the most sanguine ex- 
pectations of its projectors; and the use of the portable gas 
lamp, invented by our townsman, David Gordon, Esq. is 
hourly extending, and will soon be in general use, wherever 
oil gas is manufactured. Companies have been formed, and 
extensive machinery is manufacturing for Paris, Rouen, an 
