92 FARMER'S REGISTER— MOVEMENT UPON CANALS— RAIL ROAD. 



of such marl of more use as a manure, than that of 

 limestone, which is generally sand or clay. 



Shell marl may be converted into quicklime by 

 burning. Its solution changes vegetal)le colors to 

 green, and it possesses all the other properties of 

 quicklime, and, as such, is used for building in 

 many places of England. 



De Pages, in his travels, mentions that the in- 

 habitants of the South Banks of the INIississippi 

 make oyster shells serve all the purposes of hme- 

 stone. And lands that receive manure from towns 

 where much shell-fish is used, or that have shells 

 in their soil, naturally, or by being brought to them 

 from a shelly seashore, stand in no need of lime 

 for their culture, and are not at all benefitted by it. 



Some naturalists, indeed, believe that all lime- 

 stones, marbles, and other masses of calcareous 

 substances, are derived from the remains of ani- 

 mals, and consolidated either in consequence of 

 fusion by heat, or solution in water ; and some of 

 the finest limestones and marbles show, unequivo- 

 cally, that they are a congeries of shells of the 

 ocean. Beds of these materials are frequently 

 found near the summits of mountains, in which 

 the shells that compose them can be distinctly 

 traced and enumerated by the naturalist. 



As a manure, shell marl uncalcined is therefore 

 to be used as lime ; but in that state, it is not so 

 minutely divisible, nor so soluble in water, and of 

 course more tardy in its operation ; of consequence, 

 however, it remains much longer in the soil than 

 quicklime. On the comparative value of shell 

 marl and lime, Mr. Lummis, in an essay quoted 

 in Maxwell's Husbandry, remarks, ' Notwith- 

 standing that lime is so very good manure, yet I 

 f)refer marl to it; because, lasting five times as 

 ong, it is in the end much cheaper, although some- 

 times it is more chargeable at first than the other.' 

 Likewise, it is obvious that the quantity of calca- 

 reous matter in a boll of shell marl is more than 

 double that in a boll of powdered quicklime. — 

 The price ought therefore to be more tha;; double, 



Interest i Hg £x per intent. 



ACCELERATED MOVEMENT UPON CANALS. 



On Saturday afternoon a trial was made upon 

 the Paddington canal, of the new canal-boat. — 

 The object of the trial was, to show that a boat 

 built in a different form, and constructed of other 

 materials than the ordinary canal-boat, might, by 

 using superior horses, be drawn along the water 

 at the rate of ten miles or more in an hour, in- 

 stead of two miles an hour, the pace of the boats 

 now in use. The day was i-emarkably fine. The 

 portion of the CEUial more particularly appropriated 

 to the experiment was from the third to the seventli 

 mile from Paddington. The boat was constructed 

 of sheet-iron, riveted hot. It was 70 feet long by 

 5^ feet wide ; and painted green and white. The 

 boat was provided with an awning made of white 

 twilled cotton cloth, which had been rendered 

 semi-transparent with oil. The awning was so 

 set up that the top was extended over light wooden 

 arches, which rested upon a thin upright frame of 

 rod iron ; and the sides, in the form of curtains, 

 were made to slide at pleasure upon parallel rods 

 placed at the upper and lower ends of the curtains. 

 The rudder was of a single sheet of iron, of about 

 a yard in length, and it was moved by a tiller 

 made of about two yards of stout rod iron. Two 

 (Steady hunting horses, each mounted by a lad, and 



the two harnessed to a towing rope of about 150 

 feet in length, constituted the moving power. The 

 number oi' persons on board the boat was 48, in- 

 cluding the crew, the gentleman making the ex- 

 periment, some of the principal members of the 

 Grand Junction Company, and the visiters, among 

 whom were Mr. Telford, Mr. Babbage, Captain 

 Basil Hall, Mr. Hellyer, and Mr. Gill ; a lady 

 also made one of the party on this interesting oc- 

 casion. Certain distances were measured on the 

 canal bank, and marks set up at the ends of them. 

 At each of these places also, a man was stationed, 

 with a guaged rod in his hand, which he so held, 

 as that, upon the boat's passing, he might instantly 

 read off the height of the wave caused by the dis- 

 turbance of the water. When all things were 

 ready on the shore, and the party had embarked, 

 the boat was put in motion. The speed from one 

 station to another, taken by seconds watches, show- 

 ed, for some time, a progress at the rate of thirteen 

 miles an hour. The horses, however, soon began 

 to tire, and the speed fell to eleven, and ultimately, 

 in returning lor the third time, to ten and quarter 

 miles in the" hour. 



The experiment, as far as it goes, was attended 

 with complete success. The motion is the easiest 

 imaginable. The boat glides along the water so 

 smoothly and noiselessly, that its progress is all 

 but imperceptible to those on board, whose atten- 

 tion is not extended to external objects. A relay 

 of horses w ill be required at the end of every four 

 or five miles. The banks of the canal will have 

 to be edged for nine or ten inches above the ordi- 

 nary level of the water with hai'd materials, and 

 the towing path to be slightly sloped outwards. — 

 Improvements, no doubt, will also be made to fa- 

 cilitate the passing of locks, and in the mode of 

 attaching the horses to the boat, so that the ani- 

 mals may exert their power upon the boat, disem- 

 barrassed of the awkwardness of the direction in 

 which, in the present form of towing, they are 

 made to put forth their strength. — ILondon jllbion. 



JVe^v Rail Road. 



The Compiler recommends the establishment of 

 a rail road between tliis city and Potomac Creek. 

 This suggestion presents itself under two points of 

 view : — 1st. Is the scheme an useful one ! 2d, Is 

 this the time for us to undertake it ,'' 



Its utility seems to be unquestioned. In conver- 

 sation on Monday last with our accomplished En- 

 gineer, Moncure Robinson, Esq., he specified this 

 road among the most useful to the public, and the 

 most profitable to the stockholders, which could 

 be undertaken in Virginia. Among the articles 

 of transportation, he pointed out our coal — which 

 might be conveyed cheaply, and without much 

 handling and risk of breaking, to Fredericksburg — 

 and by way of the -Potomac, to Washington, Alex- 

 andria, &c. But he particularly mentioned the 

 carrying of passengers, along the great thorough- 

 fare from South to North, as one the great sources 

 of emolument to the road. The experience of the 

 Petersburg rail road, so far, shows us, thatpasseyi- 

 gers are a greater source of profit than even arti- 

 cles of transportation — and in this respect, he con- 

 tends that the Petersburg rail road will always 

 have the advantage of the Portsmouth road. For 

 example — the following are the receipts of trans- 

 portation on the Petersburg road from its opening 

 on the 28th October 1832, down to June 1st, 1833: 



