58 



SCIENCE 



[N. S. Vol. XLIV. No. 1124 



until the block becomes clear and sinks; tbis 

 may take from three days to a week. The oil 

 mixture is as follows: 



Chloroform by weight 4 parts 



Origanum oil by weight 2 parts 



Cedarwood oil by weight 4 parts 



Absolute alcohol by weight 1 part 



Carbolic acid crystals by weight 1 part 



Put some dried sodium sulphate into the bot- 

 tom of the tube to take up the water brought 

 into the mixture by the celloidin. 



8. Wash cleared block in three or more 

 changes of benzol; this takes out oils and 

 alcohol, and prepares for paraffin infiltration. 



9. Infiltrate in paraffin, and embed. The 

 temperature of the bath and long duration of 

 infiltration will not cause shrinkage, as Apathy 

 states that blocks left in a bath at 70° C. for a 

 week showed no shrinkage. To insure good 

 ribbons I find a paraffin of medium hardness 

 satisfactory in most cases, and leave a margin 

 of pure paraffin about the celloidin-paraffin 

 block when trimming. Where hard chitin is to 

 be cut and the firmest possible block is desired, 

 I use hard paraffin to infiltrate, and cut with a 

 slanting knife on a sliding microtome. 



10. Section and mount, using Mayer's fixa- 

 tive; then spread out and affix by warming as 

 for paraffin sections. In staining on the slide, 

 avoid leaving for any great length of time in 

 xylol or absolute alcohol, as these liquids will 

 dissolve the celloidin. A clearing oil instead 

 of xylol may be used to advantage before the 

 balsam. When objects stained in bulk are 

 used, merely remove the paraffin in xylol and 

 mount in balsam. S. I. Kornhauser 



Zoological Laboratory, 

 Northwestern University 



the asphyxiation of cancer 



Granting, at the present time, that early 

 surgical removal is the most satisfactory 

 method of curing cancer, there still remains 

 the " hope which springs eternal in the human 

 breast " of the scientist that a day will come 

 when a successful non-surgical treatment of 

 cancer may be realized. For centuries compe- 

 tent investigators have been seeking this goal, 

 but without avail. With the exception of toxic 

 gases, practically all of the possible chemical, 



physical and biological agents have been tried, 

 including cell poisons, caustics, electricity, 

 heat, light (visible and invisible rays), "vac- 

 cines," sera, and cell or organ extracts. The 

 chief difficulty has been the finding of an 

 agent which has a specific destructive action 

 on the cancer cell without an injurious effect 

 upon the surrounding healthy tissues. It 

 must be admitted that a rational non-surgical 

 treatment awaits the demonstration of a spe- 

 cific causal agent, or of a logical explanation 

 of such an abnormality based on a thorough 

 study of the chemistry and physics of proto- 

 plasm in general and of the living cell in par- 

 ticular. 



A working hypothesis concerning the cause 

 of cancer has been formulated by the writer 

 after several years of theoretical and practical 

 study. According to this hypothesis cancer is 

 the result of localized, unchecked, over-com- 

 bustion, or hyperoxidation, in epithelial cells; 

 this condition is brought about by the con- 

 centrated, accelerated and uninhibited action 

 of intracellular oxidizing enzymes, or their 

 coenzymes, as a result of various injurious 

 agents. 



Based upon this theory, a rational treat- 

 ment of the disease involves the inhibition of 

 such "hyper-oxidations," or the complete 

 asphyxiation of the cancer cells. This may be 

 attempted indirectly by attacking the intra- 

 cellular oxidizing enzymes (upon which cell 

 oxidations, growth and multiplication so 

 largely depend) or by renewing those enzymes 

 in the body whose function it is to combat 

 injurious cell oxidations. The direct asphyxi- 

 ation of the cancer cell involves (1) the with- 

 holding of oxygen (so necessary for cell life) 

 either by cutting off the blood supply or by 

 absorbing the oxygen itself before it can be 

 of service to the tumor cells ; or (2) the intro- 

 duction of sufficient carbon dioxid, or other 

 toxic gases, to cause the suppression of oxida- 

 tions in the tumor cells. It is evident that 

 such a treatment must be confined to the can- 

 cer cells, for the general effect would be to kill 

 all of the body cells. Herein lies the chief 

 difficulty in its practical application. 



Experimental work, involving the above 



