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some rudely chipped flints as infallible evidence of the fact. The 

 wing of a fossil Cockroach (Blatta) has lately been found in the 

 middle Silurian rocks in France, so our domestic friend, with whose 

 presence we could so well dispense, proves to be the oldest of all 

 known fossil insects. Another Frenchman, a M. Ramus, is able to 

 assure us possitively that man has been in existence on the earth 

 exactly 223,108 years, and I think we must admit that the exacti- 

 tude of the odd eight years renders this a fact not to be doubted. 



Mr. Galton's " Composite Photographs " are exciting a good deal 

 of scientific interest, giving, as they do, much valuable information 

 as to the physiognomy of different classes and races of men. It has 

 been recently discovered too that the aid of Photography can be 

 dispensed with and composite portraits obtained on the principle of 

 the Stereoscope. Thus a compound portrait of a girl of twenty and 

 her grandmother was found to resemble neither of them so much as 

 the face of the mother whose age was about forty. 



I dare say most of you know Galton's method is to take negatives, 

 of exactly the same size, of a number of different persons of the 

 same class, say for example, naturalists, painters, or doctors, who 

 must all have the eyes fixed on precisely the same spot. Each 

 negative is then lightly printed on the same sensitized paper, one 

 on the top of the other, In this way only the salient points of each 

 face are transferred to the paper, and some very interesting results 

 are obtained. Few people are aware what good service the 

 Japanese are rendering to science, not only in their careful 

 chemical experiments but by their exact observations of earth- 

 quakes, earthtremors, and deep temperatures. They have devised 

 a method by which movements of the earth are made, by means of 

 suitable instruments called seismographs, to draw their own move- 

 ments on paper, thus showing their direct extent ; not only have 

 they done this, but by an invention eminently practical and useful 

 in such an earthquake area as Japan, they have contrived a method 

 of counteracting and preventing the disastrous consequences of 

 earthquakes on buildings. This is done by resting the foundations 

 of the houses on small cast-iron shot, of a quarter inch in diameter, 

 placed between cast-iron plates in the piers on which the houses 

 are built, aU sudden movements, which is the great source of danger, 

 is thus prevented, and the shock is expended in merely rolling the 

 shot, while the building itself is practically unmoved. 



I may here allude to the rather bold project of Mr. Starkie 

 Gardner of utihsing the intense heat of the interior of our earth, to 

 supply warmth to the exterior. Of course we all know that the 

 deeper we go beneath the earth's surface the higher is the tempera- 

 ture ; the increase of heat was formerly considered to be one degree 

 Fahrenheit for every sixty feet we descend, but some recent 



