716 



THE POPULAR SCIENCE MONTHLY. 



on the simplest principles of physiology, that 

 other essential organs, such as the skin and 

 kidneys, are relieved by the transference of 

 part of their excretory function to the bowel 

 and act with greater ease, the general vas- 

 cular system is lightened by this regulating 

 drain, and its faculty of absorbing the waste 

 products of food and work is encouraged in 

 proportion." Only persons of gouty and 

 rheumatic habit, or of tendencies to diar- 

 rhoea, dysentery, or saccharine diabetes, will 

 be likely to find fruit in any moderate quan- 

 tities to disagree with them, while dyspeptic 

 persons will find it almost wholly beneficial. 



Formation of Peat. For the growth and 

 formation of peat which is vegetable mat- 

 ter in a semi-decomposed state is required 

 a climate sufficiently moist to foster the 

 growth of the plants of the remains of 

 which it is composed, and at the same time 

 oool enough to retard, under certain condi- 

 tions, the decomposition, beyond a certain 

 point, of successive generations of those 

 plants. Accordingly, we find it most abun- 

 dantly distributed in latitudes above 45 in 

 either hemisphere. In Ireland, the peat- 

 bogs cover about one seventh of the surface. 

 Peat-bogs are classified as those which have 

 ceased to grow and those which are still 

 growing. Some of the former class must 

 be of enormous age. In many bogs in Ire- 

 land the deposit is from fifteen to thirty feet 

 deep, and in Scotland this depth is frequent- 

 ly exceeded. Each year's growth, accord- 

 ing to Mr. Kinahan, is represented by a 

 layer of lamina, and these lamina are, on an 

 average, in white turf one hundred, in 

 brown turf two to three hundred, in black 

 turf from six to eight hundred to the 

 foot. It is easy with these data to compute 

 approximately the probable age of the 

 bogs ; but the result of the calculation is 

 liable to variations according to the manner 

 in which the bog was formed ; for the rate 

 of growth is subject to many fluctua- 

 tions, not only in different bogs, but in dif- 

 ferent parts of the same bog. When two 

 layers of wood are found in peat, the lower 

 forest usually proves to have consisted of 

 oak, and the upper one of pine. Remains 

 of the great Irish deer are very common in 

 the bogs of Ireland, and human relics are 

 often found. No chronological estimates 



can, however, be based upon the presence 

 of such relics, for articles having weight 

 will easily sink through the soft mass. In 

 districts where peat is plentiful it is exten- 

 sively used for fuel, for which purpose the 

 turf is cut from the bogs in narrow rectan- 

 gular masses a foot or eighteen inches long, 

 and prepared by drying. It is not well 

 adapted for use in manufactures, for its heat- 

 ing power is low. Peat-charcoal has, how- 

 ever, been used with advantage in smelting 

 iron, and it possesses very powerful antisep- 

 tic and deodorizing properties. Consider- 

 able quantities of peat-land have been re- 

 claimed and brought under cultivation. In 

 its natural state the soil is sour and unfit to 

 promote plant-growth, but when drained and 

 treated with lime it may be brought to a high 

 degree of fertility. When the peat-bog is 

 situated near to limestone, the process of 

 reclaiming the land is cheap and the result 

 is profitable. 



A Scientific Commonplace-Book. The 



purpose of " The Scientific Roll," a new 

 serial kind of encyclopaedia, or common- 

 place-book, projected and begun by Mr. 

 Alexander Ramsay, is to cull, classify, and 

 embody in a shape conveniently accessible, 

 all the important statements of fact and 

 theory that now lie scattered and substan- 

 tially out of reach to any one man in the 

 six thousand scientific periodicals of the 

 day. The systematization of notes on this 

 plan results in a most compendious classi- 

 fication of all that is wanted in scientific 

 literature, in such a way that lines of 

 thought are suggested to the reader, and 

 facilities are offered for following them out 

 which books, as a whole, do not afford. 

 No correction is given, or comment upon 

 the views of the several authors, but each 

 one speaks for himself, and the reader is 

 left to choose to what he will hold. The 

 first volume, just published by Swan, Son- 

 nenschein & Co., London, includes the lit- 

 erature of climate, in which a prominent 

 place is given to a very interesting bibliog- 

 raphy. One of the oldest works catalogued 

 is said to have been written in the thirteenth 

 century, and was printed by Caxton, under 

 the title of " Image or Mirror of the World." 

 But, as an English journal admits in its 

 review of the publication, " it is not till 



