HARD WICKE' S S CIENCE- G SSI P. 



227 



felt cloths or sawdust, and is thus, according to the 

 inventors, made fit for use again. 



A New Fertilizer. — Many experiments have 

 beenmadeon the continent, chiefly in Germany, during 

 the last three or four years, with "Thomas Slag," 

 as a manure, the general results being highly favour- 

 able. It is not quite equal to the superphosphates 

 and precipitated phosphates for barley, oats, potatoes, 

 and sugar beet, but the latest experiments show that 

 on moorlands it is quite equal and even superior to 

 them. This slag is obtained in treating pig iron con- 

 taining a considerable amount of phosphorus by 

 the Thomas-Gilchrist, or basic, process in the 

 Bessemer converter. I should explain that such pig 

 iron is worthless for steel making by the ordinary 

 Bessemer process i.e. when the converter is lined 

 with ganister or other refractory material in which the 

 silica predominates. By using a lining containing 

 so much lime and magnesia as to render it actively 

 basic, the phosphorus when oxidized to phosphoric 

 acid at once combines with the basic lining, forming 

 phosphates of lime and magnesia. The drawback 

 to the process is the additional cost of the lining, 

 which has to be frequently renewed in consequence 

 of this combination and removal as fusible slag, but if 

 such slag obtains a sufficient market value as a 

 manure to cover this extra cost, the Thomas-Gilchrist 

 process is economical in proportion to the difference 

 of cost between the phosphoric and the purer haematite 

 pigs commonly used for Bessemer work. So far, it 

 appears that the success is more decided on the 

 continent than in this country. It would probably have 

 been otherwise were we dependent entirely on our own 

 haematite ore, but we are now shipping vast quantities 

 of such ore from the Bilbao dictrict of Spain and 

 working it within easy distance of the coast. 



MeteorologicalInstinct. — Professor Cleveland 

 Abbe has done good service to science and common 

 sense in refuting (in a lecture delivered before the 

 Franklin Institute) the popular errors — I may call 

 them superstitions — concerning the power of animals 

 to predict the weather some time in advance. He 

 attributes their migrations and hybernating habits to 

 the inherited results of experience of many past ages, 

 or to natural causes beyond their control. 



My own theory of the Southward flying swallow is 

 shamefully unpoetical. He feeds on flying insects, 

 chiefly gnats. A little observation will show that as the 

 cold weather advances from the North, these creatures 

 cease to develope to the perfect form but remain 

 dormant in their pupa and larva; stages. The swallow 

 simply follows its food, proceeding onwards and 

 southward, if necessary, across narrow straits, such as 

 the English Channel, where the opposite coast is 

 visible to the birds in high flight. Some that find 

 warm quarters and sufficient supplies on this side of 

 the Channel do not all go across. Gilbert White 



speaks of those seen in such localities as the mouth of 

 the Lewes river, near Newhaven, coming forth from 

 holes on mild days in the winter. On such days in 

 such places gnats may commonly be seen. 



Changes of weather preceded by variations of the 



; hygrometric condition of the air are undoubtedly 



I indicated a few hours in advance by both animals and 



plants. Thus swallows fly low before rain, because 



the humidity of the air damps the wings and bodies of 



! the gnats, and disables them from soaring far above the 



ground. The swallows feed accordingly. 



Benevolent Berries.— One of the most marvel- 

 lous of the popular superstitions referred to above, is 

 that concerning the holly berries. I have heard full- 

 grown people who have been educated in select 

 schools, or genteel "colleges," calmly and deliberately 

 express their anticipations of a severe winter when the 

 holly berries are abundant, and explain the ground 

 of their belief. They attribute to the holly not only 

 wonderful meteorological foresight, but also a charming 

 self-sacrificing benevolence. It knows all about the 

 coming weather, and also that the poor birds will be 

 liable to famine when their other food supplies are 

 buried by the snow. Therefore it provides for them 

 an abundant supply of its own berries to be plucked 

 from its own bosom. Dr. Taylor has collected some 

 remarkable cases in his interesting volume on "The 

 Sagacity and Morality.of Plants," but has not included 

 this. 



Sounding the "Sounding Sea." — On some 

 parts of the coast of Sumatra and the neighbouring 

 islands, the fishermen test the depth of the sea, and 

 also the nature of the sea bottom, by the noises they 

 hear on applying the ear to one end of an oar of 

 which the other end is plunged in the water. 



At a depth of 20 feet and less, the sound is a 

 crepitation, similar to that produced when salt is 

 thrown on burning charcoal ; at 50 feet it is like the 

 ticking of a watch, the tic tac being more or less rapid, 

 according to whether the bottom is entirely of coral 

 or alternately of coral and mud, or of sand. If the 

 bottom is entirely of sand, the sound is clear ; if of 

 mud, it resembles the humming of a swarm of bees. 



On dark nights the fishermen select their fishery 

 grounds according to these indications. 



Fight Between a Rat and Stoat. — The 

 following was witnessed in this parish by a farmer. 

 He was startled by the squeal of a rat in a flax dub — ■ 

 which is a place dug out for steeping lint or flax — a 

 stoat was on the track of the rat, which made for the 

 water ; the animal fastened on the rat's back, which 

 dived ; they remained under water for some time, 

 when the stoat had to come to the surface to breathe. 

 The rat shortly afterwards made his appearance, when 

 the stoat again fastened on him and killed him. — Rev. 

 S. A. Brenan, Cushcndnn. 



