132 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS or compression of the area by tight bands. Rather, baldness will occur even in skin transplanted from its usual site. Baldness is one of the so-called degenerative diseases which remain as extremely important medical problems and have not benefited from the achievements of chemo- therapeutic control of infectious diseases. It is a condition, the progress of which can be studied. The nature and therapeutic control of the disease can be investigated carefully. Findings fr6m studies of this disease may be presumed to be applicable to a number of so-called degenerative diseases, like prostatic cancer. Vitamin deficiencies in experi- mental animals certainly play an important role but whether vita- mins are of equal importance in humans is not yet so clearly estab- lished. This will be discussed in de- tail under graying of the hair. From the standpoint of local measures even the effect of shaving or cutting of hair on rate of re- growth has not been satisfactorily settled. While it is believed that shaving or cutting has no effect on the rate of regrowth and does not stimulate the fine downy hairs into becoming terminal hairs, the work is not entirely conclusive and should be repeated. The reverse of this picture is the question of whether the destruction of one hair by.elec- trolysis does not possibly stimulate other hairs of this particular hair group and as a result increase the growth of the other hairs or stimu- late follicles in a resting condition. There is competent work to show that this is the case but the majority of physicians believe that destroying one hair by electrolysis has no effect on the rate of growth of other hairs in the same group in the same patient. Again the point is not settled. The Effect of Temperature. Heat and cold are both said to influence the rate of hair growth but the effect is probably slight and brought about through the nervous system or through variations in vascularity. There are races of rabbits which tend to produce light or dark hair de- pending on the temperature in which they are kept. Radiation effects have been stud- ied and it is thought that the actinic rays--ultra violet--exert only a slight favorable action on the growth of hair but it is felt that this might be due to the hyperemia that may be produced rather than to any effect of the rays themselves. Again the matter is not settled. The x-rays alone are definitely known to stimulate hair regrowth. Large doses of x-rays or radium of course may cause either temporary or permanent hair loss but less ex- cessive doses because of their depth effect are known to stimulate hair regrowth. This can be beautifully demonstrated in cases of alopecia areata where the exposure of a small sharply demarcated portion of a large bald patch.m the x-ray results in hair regrowth in this area while the rest of the patch remains bald. With all the hair tonics, hair ex-

THE DERMATOLOGIST LOOKS AT THE HAIR PROBLEM 133 hilarators, hair restorers, and hair dressings on the market, it is start- ling that we have absolutely no definite proof as to whether any external application made to the skin or hair, has any effect on hair growth. In fact, the most careful experiments that have been done to date, and there are not many recent ones, indicate that nothing that we apply to the skin or hair appears to have any appreciable effect on the rate of hair growth and that any of the apparently bene- ficial effects noted, may be due to the massage, hyperemia, or in- creased vascularity brought about in their application. But even the question of whether beneficial effect ensues from massage in humans has not been proved. Animal ex- periments indicate that it is the massage and not the local applica- tions that are beneficial in increas- ing rate of hair regrowth. In this field alone, it would seem to me that research should be undertaken to establish once and for all, the role of local application and massage. Furthermore, studies shoald be done to determine which vehicles are best suited, physiologically and chemi- cally, and what 'types of stimulants or irritants could best be added to them to benefit the vascularity of the papilla, follicle, and hair in its life cycle. The exact shape of the hair in different races and individuals is also not entirely settled. In some races, the hairs are oval or ribbon shaped, while in others there is a tendency for the hair to approach a rectangular form, smooth ellipse, circular form, etc. It is difficult to discover this without having the hairs arranged for examination so they can be rotated under the microscope. Also just what causes naturally curly or wavy hair is not known. 'Fritsch (5) says that while curly hair behaves in general as a dominent trait, there is no definite sign of Mendelian segregation in future generations. It is possible that the characteristic bend of the follicle immediately above the ß papilla is the point where the tend- ency to curl is really imparted. Supposition but not facts! Even the pigmentation of the hair is not too well understood. Rothman and Flesch (6) reported on the isolation of a red iron pigment from human red hair. The pre- sented data indicated that it may be a complex phenolic iron compound in which the phenolic OH group is attached to a heterocyclic ring con- taining nitrogen. This pigment was not obtainable from red hair of ani- mals or from any human hair ex- cept bright red. The literature on the darkening of hair with age is meager, general, and as far as known to Steggerda (7) never quantita- tive. Two hundred and twenty males and one hundred and ninety- four females ranging in age from 6 to 18 were measured annually for 10 years in Holland, Michigan. The study showed that the head hair becomes darker by almost one unit on the Fischer-Saller hair scale with each year of age for the ages 6 to 18. No significant sex differ-