312 JAMES CRAWFORD WATT. 



Fields are shown by various sized spherules, of crystals, and of spherules and 

 crystals mixed. 



Fig. 14. Deposit of calcium carbonate by interaction of calcium chloride 

 in 1 per cent, gelatin solution with ammonium carbonate in 4 per cent, gelatin 

 solution. Spherules of various sizes are' seen. 



Fig. 15. Deposit of calcium carbonate by interaction of calcium chloride 

 in 1 per cent, gelatin solution containing o. 1 per cent, lecithin, with am- 

 monium carbonate in 4 per cent, gelatin solution containing 0.1 per cent, 

 lecithin. Note the increase in size of the spherules over those shown in Fig. 

 14. Three different degrees of fusion are illustrated in the double forms. 



Fig. 16. Deposit of calcium carbonate precipitated by sodium carbonate in 

 a 1 per cent, solution of untreated gelatin. 



Fig. 17. Deposit of calcium carbonate precipitated by sodium carbonate in 

 a 1 per cent, solution of gelatin previously treated with Yiq HC1 solution. 

 Large crystalline precipitate. 



Fig. 18. Deposit of calcium carbonate precipitated by sodium carbonate in 

 a 1 per cent, solution of gelatin previously treated with % 2 HO solution. 

 Large, markedly crystalline deposit. 



Fig. 19. Deposit of calcium carbonate precipitated by sodium carbonate in 

 a 1 per cent, solution of gelatin previously treated with Y^o HO solution. 

 The field shown in this figure was composed for some months altogether of 

 clear spherules and a few dumb-bells. The spherules here illustrated are now 

 undergoing disintegration and in their place are appearing large crystals. 

 Some debris is seen in one corner. One spherule is seen partly from the side, 

 showing its true shape to be a disc. 



Fig. 20. Deposit of calcium carbonate precipitated by sodium carbonate in 

 a 1 per cent, solution of gelatin previously treated with %048 HO solution. 

 Disintegrating spherules and new crystals are seen. 



Fig. 21. Deposit of calcium carbonate precipitated by sodium carbonate in 

 a 1 per cent, solution of gelatin previously treated with M/8192 NaOH solu- 

 tion. Newly formed crystals and various stages of disintegrating spherules 

 are shown. 



Fig. 22. Deposit of calcium carbonate precipitated by sodium carbonate 

 in a 1 per cent, solution of gelatin previously treated with iW/4096 NaOH 

 solution. 



Fig. 23. ^Deposit of calcium carbonate precipitated by sodium carbonate in 

 a 1 per cent, solution of gelatin previously treated with M/2048 NaOH solu- 

 tion. Precipitate is all in the form of small spherules which have been in 

 constant Brownian movement for six months. 



Fig. 24. A series of spherules showing various stages in the disintegrative 

 changes which occur before they redissolve. a, Spherule with small central 

 opaque area, b, Spherule with opaque radial striation extending from central 

 spot, c, Spherule with further extension of opaque area, d, Spherule almost 

 completely opaque. Narrow, bright, clear periphery, e, Spherule striated 

 right out to periphery, f, Spherule like that in d, dissolving both at periphery 

 and in center in a regular manner, g, Spherule like that in e, dissolving at an 

 irregular rate at the periphery, h, j, Remains of dissolving spherules, and 

 debris of some that have fallen apart. 



H 



