« EelmineJätka »
a large portion of which has long been known by between 1061-1068
the researches of Montague, Berkeley, De Pary, 1069-1074
and others, has recently been completed by 1075-1082 1083-1104
the discoveries and investigations of Worth1105-1109
ington G. Smith. Fig. 68, reduced from a 1110-1114
cut in the “Gardeners' Chronicle" (July 17, 1115-1119 1120-1129
1875) to one of Mr. Smith's original papers,
will give an idea of the nature and method of “If the starch alone is to be determined, de reproduction of the fungus. It represents a duct seven from the factor and multiply the very fine and successful section of the leaf of specific gravity by the number thus obtained ; a diseased potato highly magnified. A A are the result is the percentage of starch.
the minute hairs always present; B B ara “If the specific gravity of the potato is below the individual cells of the leaf. The former 1068, the quality is very bad ; between 1068- are structures belonging entirely to the 1082, the quality is very inferior; between healthy plant, whilst the threads and bodies 1082-1105, the quality is rather poor ; above shown at C, D, E, F, and G belong to the 1105, the quality is very good; above 1110, the fungus, the parasite which preys upon the quality is best.”
plant. The fine thread at C is a continuation A poisonous principle, termed solanine, is of the spawn or mycelium living inside, and at said to become developed in the buds and the expense of the assimilated material of the shoots of potatoes that are allowed to grow leaf. Emerging into the air, the thread out on keeping; but no case is recorded, not- ramifies at the tips of the branches and bears withstanding the universal consumption, of fruit, D D. These fruits are termed simple poisonous effects arising from the use of such spores, or conidia, because of their dust-like potatoes.
appearance. The conidia are capable of germiWith regard to the cooking of potatoes, the nating and reproducing the species just in best general method is, without doubt, either the same way as a seed. A second method to bake or steam them in their skins. Dr. of reproduction of the peronospora is shown Letheby asserts that when potatoes are peeled in the “swarm-spores ” E F. These, when and then boiled, the loss in cooking is 14 per moistened artificially, or in nature by dew or cent.; but if cooked without peeling, it is rain, set free fifteen or sixteen bodies known only 3 per cent.
as “zoospores," so named because they er. The Potato Disease.--In the United States hibit every phenomenon of animal and sper in 1843 a disastrous disease appeared among matozoa-like life. They are furnished with the potato crops ; in 1844 it had reached two lash - like tails, and move about for Canada, and before the end of 1855 it had half an hour with great rapidity. The 200shown itself in most European countries. spores falling upon any portion of the plant, Since that date this disease appears to have an extraordinary power of instantly have been on the increase, and it resists corroding and boring through the cellular all efforts to eradicate it. It usually ap- epidermis. When movement ceases, the tails pears in July, August, September, and Oc- (cilia) disappear, the zoospores burst at one tober, but a few crops have been attacked end, and protrude a tube which develops into in May. A mild and moist atmosphere ap- mycelium, producing, as before, the perfect pears to favour the spread of this malady, plant. These two asexual methods of reproand no soil is exempt from its attacks, though duction have long been known, but as in both sloping well-drained soils are always the least of them the structures are far too delicate to affected. An abundance of manure, especi- withstand the frosts of winter, it was difficult ally if directly applied, often corresponds with to account for its winter life until Mr. Sun:th the maximum intensity of the plague ; and showed that the third mode of reproducagain, the potatoes only lightly covered by tion, already made out in similar species of the soil have frequently been those most peronospora, was also to be found in the violently attacked. No variety has been able potato plant. The third form is a true to resist this disease, though one or two have sexual method, perfectly analogous to the in a measure succeeded in escaping its influ- reproduction of the higher flowering plants. ence. It commences in the leaves of the This third method is the production of ea plant, and thence extends from the stem to shaped bodies, about oto of an inch in the tubers. On the surface of the latter diameter, known as “oospores.” The cesperts brown spots make their appearance, penetrate are produced by the conjugation of two the substance, and eventually lead to decay. bodies — the one, the male, known as the
The disease is caused by a minute fungus antheridium (see H, fig. 68), and analogous to called Peronospora infestans. The life-history, the anther of a flower; and the other the
oogonium (J), the female, analogous to the The cospores are not transparent and unendurovary of a flower. The antheridium and ing, but dense in substance, of a dark brown oogonium have been seen in contact, and a colour, and covered externally with reticulafertilising tube from the former has been tions or warts. “They are produced from observed entering the oogonium. After fer- the mycelium by the contact of the antheritilisation the oogonium develops into the dium and the oogonium in the substance of cospore analogous to the matured seed. This the decaying ant. They are washed into third method only appears to take place in the earth, and there they rest till a certain the rotten and decayed parts of the plant. set of conditions makes them germinate in
the year following their production, just as a destroying the potato, since the life of the seed falls and rests in the autumn, and starts fungus is passed within the very tissues itself. again into life during the following spring."— There is one thing, however, evident-viz., (W.G. SMITH.)
that destruction by fire of all diseased haulms Although we now possess the last link in the would without doubt check the disease very chain, and know probably the entire history effectually; that it would extinguish it altoof the fungus, the remedy is not so clear; for gether is doubtful, for it is certain that the the parasite in the living plant can hardly be potato plant is not the only one affected with reached by any destructive agencies without I the peronospora, and if therefore the whole of
the diseased potato plants in the world were and if necessary seize, poultry. See FOOD, INdestroyed, in the next season the fungus might again invade the crops from other solanaceous plants.
Poverty-See PAUPERISM. Potato, Sweet-See BATATA.
Powers of Sanitary Authorities,
See SANITARY AUTHORITIES. Poultry - Poultry usually contains too much nitrogenous matter and too little fat to Preserves — Preserved fruits – jams, be very nourishing. The duck and the goose, jellies, &c.--frequently contain copper, and which possess more fat, contain certain flavour- in some cases this metal has been found to be ing matters which are not easy of digestion. present in large quantities. It is derived No bird nor bird's egg is known to be poison- either from the copper vessels in which the ous, but some birds are rendered poisonous preserves are often prepared, or has been by the food which they have eaten. The added to improve the colour of the article. pheasant, for instance, which feeds on the See COPPER. buds of the Calmia latifolia, in North America,
Prevention of Disease - Sec Epiis deemed poisonous during the winter and
DEMIO, &c. spring; and birds in this country which have fed on poisoned grain have produced serious Prices—The prices of the principal prosymptoms in those who have eaten them. visions have greatly increased since 1852. The A medical officer of health, &c., may inspect, following table clearly shows this :The AVERAGE PRICES of Consols, of Wheat, of Meat, and of POTATOES in each of the
Twenty Years 1852-1871.
Average Prices of
Best Potatoes per Ton
at Waterside Market,
Prison Diets-See DIETARIES.
fication, which may be modified to suit par
ticular circumstances, are given on pp. 468 Privies — It would be well for sanitary 466. authorities to select, in every case, properly- There is no privy yet constructed that will designed plans of privies, and to enforce by- give satisfactory results with dirty and carelaws ordering that no privy be erected which less people ; but when an owner provides his is constructed imperfectly or built in an im- houses with fit accommodation, there is an proper place. A very useful plan and specie i obligation then on the tenant to keep it properly attended to. The ordinary privy, with cases be superseded by either earth-closets, or an open cesspit at the back of it, should in all if a cesspit is preferred, it must be properly
ventilated, and have walls perfectly water-, either furnished with handles or on wheels, tight. The forms of privies are innumerable : and put close up to an ordinary seat: this is the simplest is perhaps a galvanised zinc pan, emptied when necessary.
Specification. The privy and dust-bin to be built ner from the owner the expenses incurred by of 43-in, brickwork, in well-ground mortar, of ap- them in so doing, or may by order declare the proved quality.
same to be private improvement expenses: Two rows of 44 and 3 in. bond timber to be built provided that where a water-closet, earthin at back of privy for securing ventilating-shafts.
The ventilating-shafts to be 7 by 44 in., inside closet, or privy has been and is used in commeasurement, of best red deal boards 1 in, thick, mon by the inmates of two or more houses, or closely put together, with strong white-lead paint, if in the opinion of the local authority a and well nailed and carefully seamed to the 4, and water-closet, earth-closet, or privy, may be so 3 in, bond timber.
used, they need not require the same to be These shafts to have coats of boiled tar both inside provided for each house.—(P. H., 8. 36.) and out.
Any enactment in force within the district The lid of refuse-bin to be of best l-in, red deal boards, with two strong ledges or battens across
of any local authority requiring the constructhem; to be hung with three strong band hinges to
tion of a water-closet shall be deemed to be the sides of the ventilating-shafts, and the making. satisfied by the construction, with the apup piece between the same. A circular orifice to be proval of the local authority, of an earth-closet. made in centre of lid, between the battens, 10 in, Any local authority may, as respects any wide. The lid to have two coats of boiled tar both house in which any earth-closet is in use with inside and out. A 41 and 3 in. frame, of red deal,
to be securely water required by any contract or enactment
their approval, dispense with the supply of fixed on top of the dust-bin as a seat for the lid.
A lid over the privy seat to be hinged on 'at the to be furnished to any water-closet in such back, with a child's seat over centre of large one. house, on such terms as may be agreed on The larger seat to be provided with an earthenware between such authority and the person procircular rim beneath.
viding or required to provide such supply of The earth compartment to be without lid, and pro- water. vided with a pint scope for each occupant to throw in a pint of the stored dry earth or dry ashes through take or contract
with any person to undertake
Any local authority may themselves underthe seat into the galvanised iron pail, the contents of which must be scattered over the garden, or put
a supply of dry earth or other deodorising in the dust-bin, before the pail becomes full. A loose substance to any house within their district foot-block may be furnished where there are young for the purpose of any earth-closet. children.
The term “ earth-closet" is to include any The dust-bin may be placed at side of the privy if place for the reception and deodorisation of required. The floor of dust-bin to be at the ground. fæcal matter constructed to the satisfaction of level, slightly inclined outwards, and paved with brick,* (Figs. 69–72.)
the local authority-(P. H., s. 37.) See als
CLOSETS, FACTORIES, NUISANCES, PUBLIC The chief provisions as to privies and
NECESSARIES, SCAVENGING. closets are as follows : It is not lawful newly to erect any house, or
Prostitution—The prevention of this to rebuild any house pulled down to or below
terrible evil has baffled the united efforts of the ground-floor, without a sufficient water. closet, earth-closet, or privy, and an ashpit, hygienist. Prostitutes have existed from the
the legislator, the philanthropist, and the furnished with proper doors and coverings.
most ancient times down to our own, and so Penalty for contravention, £20 or less.—(P. H.,
long as human nature is the same as it is not 8. 35.)
will continue to exist. The only practical If a house within the district of a local
means of in any way controlling this vige authority appears to such authority by the
within bounds is to render clandestine prostireport of their surveyor or inspector of nui- tution impossible, to register public, and to sances to be without a sufficient water-closet,
give prostitutes every facility of reforming earth-closet, or privy, and an ashpit, furnished with proper doors and coverings, the local inspection to be able to isolate and care
their manner of life, as well as by periodical authority shall, by written notice, require those who are affected by venereal disease, the owner or occupier of the house, within a
and thus prevent its propagation. reasonable time therein specified, to provide a
It is difficult to know the number of prostisufficient water-closet, earth-closet, or privy, and an ashpit, furnished as aforesaid, or either tutes, except in those few places where the
Contagious Diseases Acts are in force. In of them, as the case may require. If such notice is not complied with, the and open prostitutes are known to the police;
London, for example, only the more notorioa local authority may, at the expiration of the and it is evident that clandestine prostitutice, time specified in the notice, do the work re
which is known to exist to a considerable quired, and may recover in a summary manamount, will always render official retures
* The above forms can be obtained of Knight & inaccurate. The following table, boweser, Co., 90 Fleet Street, London,
gives some idea of London prostitution :