784 PRACTICE OF AGRICULTURE. Part III. 



ing them in deep pits, and laying them upon the surface. Camps are of various sizes ; 

 being too frequently made in a long square form like a corn-rick, and of a size propor- 

 tioned to the quantity to be laid up. It has, however, been found by experience, that 

 when the quantity is large, they are liable to heat and spoil; much damage having some- 

 times been sustained by this imprudence. Experienced campers hold that a camp should 

 not be more than three feet wide ; four feet is perhaps as wide as it can be made with 

 propriety, proportioning the length to the quantity ; or, if this be very large, forming a 

 range of short ones by the side of each other. The usual depth is a foot. The bottom 

 of the trench being bedded with dry straw, the potatoes are deposited, ridging them up 

 as in measuring them with a bushel. On each side the roof long wheat straw is laid, 

 neatly and evenly as thatch ; and over this the mould raised out of the trench, is evenly 

 spread ; making the surface firm and smooth with the back of the spade. A coat of coal 

 ashes is sometimes spread over the mould, as a still better guard against frost. It is 

 needless to observe that a camp should have a dry situation ; and that the roots ought to 

 be deposited in as dry a state as possible. These camps are tapped at the end, some 

 bavins, or a quantity of loose straw being thrust close in the opened end, as a bung or 

 safeguard. As it is a matter of the highest importance to preserve this root without 

 spoiling during the whole year, it has been suggested, that the best method yet discovered 

 for keeping potatoes sound for the longest period, is to spread them on a dry floor early in 

 the spring, and to rub off the eyes occasionally, as they appear to have a tendency to push 

 out ; by using these precautions, Donaldson has frequently seen potatoes kept in good 

 condition till the month of June. 



4862. In Canada and Russia the potatoe is preserved in boxes in houses or cellars 

 heated to a certain temperature by stoves. {Farm. Mag. vol. xx. p. 449.) 



4863. To keep potatoes any length of time, the most effectual way is to place them in 

 thin layers on a platform suspended in an ice cellar. There the temperature being 

 always below that of active vegetation they will not sprout, while not being many degrees 

 below the freezing point the tubers will not be frost bit. Another mode is to scoop out 

 the eyes by a very small scoop, and keep the roots buried in earth. A third mode is to 

 destroy the vital principle by kiln drying, steaming, or scalding. 



4864. The ])roduce of the potatoe varies from five to eight, and sometimes ten or 

 twelve tons per acre ; the greatest produce is from the yam, which has been known to 

 produce twelve tons or 480 bushels per acre. The haulm is of no use but as manure, 

 and is very generally burned for that purpose, being slow of rotting. 



4865. The ajiplication of the potatoe crop of the greatest importance is as human food, 

 on which it is unnecessary to enlarge. EinhofF found mealy potatoes to contain twenty- 

 four per cent, of their weight of nutritive matter, and rye seventy parts. Consequently 

 sixty, four and a half measures of potatoes afford the same nourishment as twenty-four 

 measures of rye. A thousand parts of potatoe yielded to Sir H. Davy from 200 to 260 

 parts of nutritive matter, of which from 155 to 200 were mucilage or starch, fifteen to 

 twenty sugar, and thirty to forty gluten. Now, supposing an acre of potatoes to weigh 

 nine tons, and one of wheat one ton, vi'hich is about the usual proportion, then as 1000 

 parts of wheat afford 950 nutritive parts, and 1000 of potatoe say 230, the quantity of 

 nutritive matter afforded by an acre of wheat and potatoes will be nearly as nine to 

 four ; so that an acre of potatoes will supply more than double the quantity of human 

 food afforded by an acre of wheat. The potatoe is perhaps the only root grown in Britain 

 which may be eaten every day in the year without satiating the palate, and the same 

 thing can only be said of the West India yam, and bread fruit. They are, therefore, 

 the only substitute that can be used for bread with any degree of success, and indeed they 

 often enter largely into the composition of the best loaf bread without at all injuring 

 either its nutritive qualities or flavor. {Edin. Encyc. art Baking.) In the answer by 

 Dr. Tissot to M. Linquet, the former objects to the constant use of potatoes as food, 

 not because they are pernicious to the body, but because they hurt the faculties of the 

 mind. He owns that those who eat maize, potatoes, or even millet may grow tall and 

 acquire a large size ; but doubts if any such ever produced a literary work of merit. 

 It does not, however, by any means appear that the very general use of potatoes 

 in our own country has at all impaired either the health of body or vigor of mind 

 of its inhabitants. 



4866. The meal of potatoes may be preserved for years closely packed in barrels, 

 or unground in the form of slices ; these slices having been previously cooked or dried 

 by steam, as originally suggested by Forsyth, of Edinburgh. {Encyc. Brit.) Some 

 German philosophers have also proposed to freeze the potatoe, by which the feculous mat- 

 ter is separated from the starch, and the latter being then dried and compressed, may be 

 preserved for any length of time, or exported with ease to any distance. {Annalen des 

 Ackerbaues,yo\. iii. s. 389.) 



4867. The ordinary economical applications of the potatoe, next to those of the culinary 

 and baking arts, is in starch making and the distillery. Starch is readily made from the 



