Jane 26, 1866. ] 



JOURNAL OF HOETICULTOBE AND COTTAGE GARDENER. 



Selaginollas, and filled with Roses, Dracmnas, and Cordyline indi- 

 visa ; and hanjiug-baskets were also shown by Messrs. Cntbush and by 

 the Crystal Palace Company. The latter were of small size, and 

 suitable for placin;; on a table or similar position ; they were mado of 

 wickevwork, and the basket was snspeuded by a wieker chain from a 

 tripod of the same material. Other baskets were supported on small 

 greon-paintod iron tripods. The most effective esliibition in this way 

 was tho Leicester Vase, measnring from 7 to 8 feet in diameter, and 

 formed of iron ribs some inches apart ; and these being turfed over, 

 the vase was filled with a row of Colons Ver^chalTelti, then with Gera- 

 niums, Mignonette, and Hydrangeas, with a tall pyramicUil Fuchsia 

 in tho centre. 



Eoses in pots were not in the fine condition that they were seen 

 earlier in the season. The best twenty-five came from Messrs. Paul 

 and Son, Mr. Turner boinR second, and Messrs. Francis thu-d. Messrs. 

 Paul & Son also received a first prize for the best twelve sent out in 1865. 



Among miscellaneous subjects were Variegated Maize and several 

 pretty tricolor-leaved and Zouale Pelargoniums from Messrs. Carter 

 and Co. ; and Messrs. Downio Laird, & Laing, exhibited Wiltshire 

 Lass, a remarkably fine pink variety, which has already been noticed 

 in these columns ; fancy and bedding Pansies, of which Imperial Blue 

 was very attractive ; au unnamed Zouale Pelargonium with leaves 

 5 inches across, pale green, marked with a bronzy zone ; and Stanstead 

 Kival, with very largi! salmon scarlet pips. Mr. T. Smith, Lon" 

 Wittenham, exhibited a Delphinium, called Smithu, with largo deep 

 blue flowers with a white eye ; and Mr. S. Brown, Sudbury, Invin- 

 cible Swoet Pea and some pretty early-flowering Gladioli. The most 

 striking of these were Insignis, rich salmon, blotched on three petals 

 with bright violet ; Eclipse, pink and white, and Incomparabilis, 

 cream and violet crimson. 



•175 



A GLANCE AT THE FLORA OF THE 

 CARBONIFEROUS PERIOD. 



ET DR. noiUTIO 0. WOOD, JUN., PHILADELPHIA. 

 Head before Pcnmi/lvania BorticulUiral Society, Autimt, 1865. 



CsE of the most curious and interesting discoveries of 

 modern science is ihat of the voyetable origin of coal. It has 

 become so familiar to us — we are so used to looking on great 

 heaps of coal, and remembering that ages ago they were formed 

 from vegetable matter — that nothing can be more trite than 

 this opening sentence. Yet it is a wonderful discovery, one 

 that awakened strange emotions in the breasts of the earlier 

 investigators, and carried them back, in fancy, to the untold 

 ages buried in the abyss of the past — to the waving forests and 

 thick brakes of that olden time. In the light of more modern 

 science, the fact is still more strangely interesting, as affording 

 an unanswerable example of the indestructibility of a force. 

 For whence did those plants receive the power to draw the im- 

 mense mountains of carbon from the air and earth, but from 

 the rays of the olden sun ? It takes no vivid fancy to see in 

 the glowing, burning coal, the sunlight of a day long fied ere 

 man was : for science, stranger than fiction, can actually mea- 

 sure the power drawn so long since from the sun, and stored 

 away deep in tho bowels of the earth, to minister to man's 

 wants. This is not the place to do more than allude to this 

 modern doctrine of the convertibility of force, and its inde- 

 structibility. It would be a pleasant task to show how the 

 plant lays hold of the chemical part of the sun's rays and 

 binds them in its cells, making those wondrous little entities 

 so many prison-houses of force. But our task is with the Flora 

 of the carboniferous period, and we must hasten on. 



If we subject wood to the action of a slow fire, in the ab- 

 sence of a sufficient supply of air, charcoal is formed, the phy- 

 sical characters of which you are all familiar with. Inter- 

 mingled with tho coal are foimd small masses of charcoal, 

 closely agreeing in external appearance with that from the 

 Jersey Pines. Further, in and all about tho coal are vegetable 

 Teli(jike in vast abundance and endless variety: huge trunks, 

 many feet in length ; innumerable impressions of Ferns ; seed- 

 vessels, fruits, leaves, roots — yea, sometimes the stumps of 

 whole forests ; and in one or two places on the coasts of Nova 

 Scotia, the forests themselves, standing erect, imbedded in the 

 solid rock. The coal measures are, in truth. Nature's herba- 

 rium, where she has stored away the history of the botany of a 

 wonderful period — a botany with strange, weird plants, worthy 

 to grow side by side with the winged saurian lizards, and huge, 

 uncouth, ferocious sea monsters, which make our largest and 

 fiercest reptiles seem but playthings. 



The two crowning decisive proofs of tho vegetable origin of 

 coal are the following : — First, the fact that if thin slices of it 

 are properly prepared and examined with the microscope, a 

 peculiar structure is visible, so closely resembling that of ex- 

 istent plants, that we often can assert not only tho source from 



which it has come, but even the classes to which tho com- 

 ponent plants belonged. Second, the circumstance that the 

 first stage of the formation of coal is at present going on. 01 

 this more will be said after the discussion of the climate and 

 conditions imder which the carboniferous vegetation nou- 

 rished. 



Many things have been said and written about tho climate 

 of the coal ago— some of them more strange and wonderful 

 th.in even tho truth itself. Men have laid hold of the axis ol 

 tho earth, and turned it to suit their purposes and theories. 

 The great difficulty lies in the existence of coal in Mehille 

 Island, Lat. 7.5' N. The plants brought from that locality 

 seem to be similar, indeed often identical with those found in 

 our coal measures. 



Tho iiniuiry at onco arises in every thinking mind. How 

 could these plants have lived and flomished in that region of 

 ice and snow— that home of frozen death, C(dd Winter's 

 favourite resting place? Tho only plants which now grow 

 there are the hardiest of tho Alpine flora— even tho Birch and 

 the WiUow are fain to content themselves with creeping along 

 the ground, not daring to raise their heads more than a few 

 inches into that chilling air ; but tho coal shows that a flora 

 must have existed there formerly worthy to rival that of the 

 tropics in its luxuriant abundance. Whence, then, tlie heat and 

 Hght to foster and nourish such a vegetation ? In order to 

 accoimt for the existence of coal so near tho pole, Messrs, 

 Linclley and Button, two of the most famous investigators in 

 fossil botany, invented the monstrous theory, that the axis of 

 the earth had a different inclination formerly from what it hag 

 at present ; but where in Nature have we any evidence of such 

 gigantic change — a change which would involve in its influence 

 not merely our globe and its satelhte, but all our solar system? 

 Let us, then, see if it is necessary to overstep tho bounds of 

 reason to explain this problem. That coal could not at 

 present be formed in those regions is self-evident. In that 

 primaeval age there must have been more light, and especially 

 more heat there. 



What is tho great equaliser of the temperature of the earth 

 at the present day ? No doubt the air has much to do with 

 the climate. No doubt it is the hot sirocco-breath of the 

 Saharau fiu-nace, tempered by great draughts from tho Medi- 

 terranean, which gives southern Europe its genial climate, 

 and ripens the Grape on tho banks of tho Vine-clad Rhine. 

 But is not water a more powerful modifier of the temperature 

 of a country than the air ? Is it a curious fact, that if yon 

 take a pound of water at 60' Fah., and a pound of lead at 60" 

 Fah., and heat them to 120' Fall., you will find that it haa 

 taken about twice as much fuel to bring the water to that tem- 

 perature as to bring the lead up. Again, if you take these 

 heated bodies, and measure the heat given ofl' during cooling, 

 you will find that tho water has given off about twice as much 

 as the lead. The thermometer does not indicate the amount 

 but the di'ijrei; of heat in a body, and water actually reipiires 

 twice as much heat as the same weight of lead, to raise it to 

 any given temperature. If you pour on a mass of granite a 

 gill of water, the stone wiU at once appear wet ; but pour a gill 

 of water on a brick fresh from tho kiln, and it will all soak 

 into the brick, and, hid away in the interior, will give no token 

 of its presence. The absorbing power of tho brick is much 

 greater than that of the stone. So it is with water and heat. 

 The Creator has given to water a great power of absorbing 

 heat and hidhig it away in its interior. Is it not evident how 

 this property fits it for being the great equaliser of the earth's 

 temperature? It is notorious, that in the winter tho sea-coast 

 is not so cold as the inland, whilst in summer it is not so hot. 

 The reason of this is, that the water absorbs tho hoat of the 

 one season, and gives it off to moderate the cold of tho other. 



Glance for a moment at a map, and you will see that the 

 gloomy, frozen coast of Labrador — the native home of tho 

 seal and the iceberg — is in the same latitude with the fertile 

 England, with its mild climate and busy midtitudo of men. 

 The groat cause of .all this difference is the Gulf Stream, that 

 great oceanic river, ever flowing from the Tropics and strand- 

 ing itself on Northern Europe. It is mado up of millions of 

 drops of water, and each sparkling drop is a little casket with 

 its treasure of heat looked up within it. From tho fierce 

 burning sun of tho tropics it receives it, and hurries away 

 with it to mako fertile and inhabitable tho western shores o£ 

 the Old World. 



As water is thus tho great equaliser of climates, tho great 

 distributor of equatorial heat, it is easily seen that if the sur- 

 face of tho globe was almost covered with water, tho extremes 



