898 



SCIENCE 



[N. S. Vol. XLI. No. 1068 



statesmen. Of the eleven writers of fiction, 

 nine were elected, while, of the ten authors 

 who wrote on serious subjects, only three were 

 chosen. As the judges are men of literary 

 tastes, they were more familiar with the work 

 of the authors than of men in the other 

 classes. The uniformity of the percentages in 

 different years is very marked. This renders 

 more conspicuous the relatively small vote for 

 authors in 1900. If forty votes had elected in 

 1910, three of the six who were chosen would 

 have been statesmen. 



As the total number of votes east was 8,645, 

 three fourths of them were wasted ; 2,050 votes 

 would have given the forty-one men elected 

 fifty votes each. 



Edward C. Pickering 



May 25, 1915 



A METHOD FOR IMBEDDING SMALL OBJECTS 



It is quite a task to carry minute objects, 

 as protozoa or eggs of sea urchins, etc., through 

 the alcohols and get them safely imbedded in 

 paraflS.n, without losing most if not all of 

 them on the way. Lefevre^ described a watch 

 crystal designed by him for the purpose of im- 

 bedding small objects. This crystal had a small 

 rectangular-shaped slit in the bottom about 

 12 X 2 X 3 mm. This could be given a thin 

 coat of glycerine and the objects placed in it 

 by means of a pipette, and then the melted 

 parafiSn poured over them. When cold the 

 paraffin can be removed with the objects im- 

 bedded in the small rectangular block which 

 is easily trimmed for cutting. Lefevre sug- 

 gested that the objects might be carried 

 through the dehydration stages in the crystal, 

 by drawing off the liquids with a pipette. This 

 however, as later pointed out by Mayer, would 

 remove the possibility of coating the crystal 

 with glycerine and hence make it nearly im- 

 possible to remove the paraffin block when cold. 

 Mayer^ suggests an improvement by transfer- 

 ring the objects from absolute alcohol into 

 small gelatine capsules. They may be cleared 

 with xylol in the capsule and then melted 



1 The Jour, of Applied Microscopy, Vol. V., pp. 

 2080-2081. 



2 Zeitschr. f. wiss. MiTcrosTc. u. mihr. TechniJc, 

 Bd. 24. 



paraffin added, and the whole thing cooled in 

 water. The water cools the paraffin and also 

 dissolves away the gelatine capsule, leaving 

 the objects imbedded in a neat cylindrical plug. 

 There are some objections, however, to this 

 method. (1) The great danger of losing the 

 objects during the process of transferring them 

 with a pipette from one reagent to another, 

 and (2) the end of the paraffin cylinder at 

 which the eggs lodge is rounded and hence 

 difficult to cut. This latter obstacle was over- 

 come by Metcalf's suggestion^ of reimbedding 

 the objects in a Lefevre watch glass and hence 

 removing the difficulty of having a round end 

 to the mold. He found this successful with his 

 preparations of Opalina. But even still there 

 is great trouble attending the dehydration of 

 these small bodies by transferring them from 

 one watch crystal to another with a pipette or 

 by drawing off the liquids with the pipette and 

 leaving the objects in the dish. To make this 

 task easier I suggest the following method 

 which I have found successful with the eggs of 

 sea urchins and Oereiratulus lacteus. 



A heavy wooden base is obtained with holes 

 bored in it of a proper size to permit ordinary 

 homeopathic phials to stand upright in them. 

 The size of phial I have found most conveni- 

 ent is about ten centimeters long and three in 

 diameter. These phials are fitted with corks 

 and then filled with the reagents desired in 

 the process of fixation and dehydration. The 

 next step in the preparation is to get some 

 gelatine capsules (5 X H mm.) and give them 

 a thin coat of shellac (shellac dissolved in 98 

 per cent, alcohol). This coat is best applied 

 by immersing the capsules for a minute in 

 a thin solution of the shellac and then stand- 

 ing them up on a flat surface to dry. Care 

 must be taken to see that the capsules are 

 completely immersed in the shellac solution so 

 as to insure the coating of the inside surface. 

 "When dry take a fine needle and heat the point 

 red hot and with it pierce a hole in the wall 

 of the capsule about two millimeters from the 

 top and another about three millimeters from 

 the bottom. This is to permit a thorough 

 drainage of the reagents through the capsule. 

 A fine wire can now be fastened to the rim of 



3 Arch. f. FrotistenTiunde, Vol. 13, p. 195. 



