1. It should be remembered that most of the information we have at present has been obtained by the use of one type of ionizing radiation (x-rays). It is possible, therefore, that differences in kind may be found when neutrons are used more extensively in radio-biology.
2. More recently genetic changes have been produced by other means, notably heat.
3. The ratio is approximately 1 to 2 for most of the range of the curves. It becomes about 1 to 1.5 near the end.
4. Strictly speaking the comparison should be made on the basis of energy absorbed per gram of skin in both cases. As a matter of fact there are objections of one kind or another to all the energy comparisons given here. They are intended simply to convey an idea of the orders of magnitude involved.
5. Preferably a radiologist who is familiar with such reactions.