298 ANNUAL OF SCIENTIFIC DISCOVEUr. 



son to extend the principle furtlier, and he had now advanced so 

 far that he was enabled to tninsrait light through various tis- 

 sues of the bodies of laro^e animals. He had thought it was best 



1 • 



to begin by testing each tissue separateh^ and this investigation 

 had been carried out on nearly all the structures of the body which 

 admit of being individually examined. The structure the most 

 diaphanous was the skin ; after that, and singularly enough, bone ; 

 then thick membranes ; next, thin superficial muscles, lung tissue, 

 fat, and the dense tissues of the liver and the kidney. Various 

 lights had been tried, namely, the electric, the oxyhydrogen, the 

 lime, and the magnesium light. For all practical purposes the 

 magnesium light was the best; it was the most convenient to use, 

 and the light had the advantage of penetrating deeply. In the 

 lantern which Dr. Richardson exhibited, the light was also unat- 

 tended with heat at the point of observation, so that the hand 

 could be put in at the brightest illuminating-point. The additions 

 consisted in a tubular arrangement and a sliding groove. The 

 structure to be examined was placed in the groove enclosed be- 

 tween two disks of perforated wood, and the object was surveyed 

 from the further end of the tube. A thick piece of bone, the flat 

 rib of an ox, was placed in the lantern, and light was distinctly 

 transmitted through it by way of illustration. It might be used 

 for a variety of physiological purposes. Animals whose tissues 

 were thin, such as fish, could be placed in the lantern, and the 

 condition of their circulation and respiration could be carefully 

 studied under the action of various agents. In the human sub- 

 ject, especially in the young, with fragile tissues, the thinner parts 

 of the body could be distinctly rendered transparent; and, in a 

 child, the bones, with a somewhat subdued light, could be seen in 

 the arm and wrist. A fracture in a bone could in fact be easily 

 made out, or growth from bone in these parts. In a very thin, 

 young subject, the movements and outline of the heart could also 

 be faintly seen in the chest, but the light he had as yet employed 

 had not been sufficiently powerful to render this demonstration all 

 he could desire. It would be possible, lastl}', to see through some 

 diseased structures so as to ascertain whether, within a cavity, 

 there was a fluid or a solid body. 



ON THE PROPER USE OP GRAIN. 



The following are extracts from a letter by Baron Liebig, copied 

 into *'Dingler*s Journal" from the Augsbm'g "Zeitung" : — 



" In view of the present distress of the poor inliabitants of East- 

 ern Prussia, it may not be inappropriate to direct public attention 

 to the fact, that grain, by its conversion into flour, loses in nutri- 

 tive properties ; that of rye by 10 per cent., that of wheat by 15 per 

 cent. 



" A grain-fruit has a structure similar to that of an egg', as in 

 the last-named the yolk, the portion rich in fat and poor in albu- 

 men, is surrounded by a layer of all)umen, so in the grain the 

 starchy nucleus is enveloped by a stratum of an albuminiferous 



