. Contributions to embryology. Embryology. CARE AND UTILIZATION OP THE COLLECTION. 33 secondary guide-lines sufficiently far outside of the proposed model not to conflict with its casting. In order that these finished plates, which we call mold plates, may be kept in exact apposition, they are piled in a rectangular corner made of plate glass (fig. 5). While this is being done it is necessary to cut certain artificial channels as vents, so that the air will escape from the openings when the plaster is poured Fio. 5.—Method of piling wax mold: i, baseboard; S, perpendicular right angle cor
. Contributions to embryology. Embryology. CARE AND UTILIZATION OP THE COLLECTION. 33 secondary guide-lines sufficiently far outside of the proposed model not to conflict with its casting. In order that these finished plates, which we call mold plates, may be kept in exact apposition, they are piled in a rectangular corner made of plate glass (fig. 5). While this is being done it is necessary to cut certain artificial channels as vents, so that the air will escape from the openings when the plaster is poured Fio. 5.—Method of piling wax mold: i, baseboard; S, perpendicular right angle corner; S, glass plate; 4, wax mold; S, vent; 6, galvanized iron wire bridge; 7, gate for plaster between parts of mold. It is also well to bridge loosely attached parts with copper wire, which is done by heating the wu-e and laying upon the wax plates as they are being piled up. The entire mass forms a mold which, to distinguish it from the others, is called a plate mold. This is cast with plaster of paris, and after the plaster has set the wax is removed by heating. Sometimes it is necessary to proceed farther and make a break mold over the first cast, after which it is possible to make as many duplicate casts as desired. In the above description the main outhnes of this valuable method of reconstruction, as now practised in this laboratory, have been given. Numerous general studies have also been made in embryometrics, in which linear, gravity, and time values are considered. Furthermore, the technique of gross anatomy has been appUed to differentiate, by means of injection, the arteries, veins, and lymphatics of the whole clarified embryo. Similar specimens can be prepared to show the entire cartilaginous and bony systems. Thus many embryos frequently are considered in a single pubhcation, especially those illus- trating causes of abortion and the production of moles and monsters. Attention is therefore called to the numbers following the references in the appended Ust of pu
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Keywords: ., bookauthorcarn, bookpublisherwashingtondc, booksubjectembryology
