French Medico-Legal Society, Draguedorff, and Woodward-give, as the average diameter of blood corpuscles, measured in the fractions of an inch, the following:25

The ordinary birds and fowls chicken, turkey, duck, pigeon. quail, dove, and sparrow-have corpuscles that are oval, measuring 1/2000 by 1/3500, roughly. While the reptiles, batrachians, and fish have distinctly larger corpuscles, measuring 1/1000 by 1/2000. When it comes to examining dried blood, however, the corpuscles are changed more or less in size and shape, and to be examined must be spread out under the microscope. To do this certain solutions must be used, and they are liable to distort the shape of the corpuscles. But the addition of fluids of less density than the blood cells, while it makes them swell up and become spherical, does not increase, but rather decreases, their diameter; and likewise fluids of greater density cause a shriveling of the cells and possibly a crenation of the cells, so that man's blood might tend to become the size of the other animals, but the blood of the other animals would not tend to approach that of man.26 Hence, a measurement of a series of cells with an average from 1/3000 to 1/3400 would exclude animals whose blood cells average smaller than 1/4000 of an inch, which would exclude the most of the domestic animals,-pig, ox, horse, cat, sheep, goat.

Whether all animals can be ruled out and the blood positively asserted to be that of man from these fine measurements has been a

"Adapted from the statistics given in Peterson and Haines' text-book of legal medicine. The figures are given in fractions of an inch, for in that form they are better appreciated by the

average juryman than in the centimeters which are used in scientific circles.

Formad, H. F., Comparative Studies in Mammalian Blood, 1888.

question of much discussion, a number of authorities being on each side. A number of the more recent authorities do consider it possible. White examined27 and measured two hundred red blood corpuscles, assigning to each a definite length, from each of a number of animals. We quote his measurements in fractions of an inch for man, dog, and pig, the animals with the corpuscles most likely to come into this field.

These measurements certainly seem distinct enough to show the difference between human blood and that of lower animals, and in many cases it is not necessary to identify the species of animal from which the blood came, but merely to say whether the blood may or may not have come from a special species of animal, or from man.

"White, Medico-Legal Journal, New York, 1894-95, Vol. XII., p. 419.

But the

And that may be determined with certainty in many cases. difficulties connected with the measurement of the red blood corpuscles in very old stains is such that the test has been considered unreliable by a number of eminent authorities; Vibert,28 Wormley, Mason,29 Ewell,30 and Chapman, among them. Hence, the distinction by this method between the different species of mammalian blood may be subject to question.

31

297. Biologic test.-In 1900 Uhlenhut32 introduced a new biologic test which has taken its place at the head of the list of tests for human blood and the differentiation of the blood of different animals. It is based upon the general principles that the animal organism generates within itself, in self defense, bodies which antagonize or neutralize injurious substances to which it has been subjected. The principle is not a new one, but has been long established in medicine, and this new test is merely a new application of well known facts. The test depends upon the fact that when the product of one animal (in this case, human blood serum) is injected into an animal of another species (a rabbit), in the course of time the blood of that rabbit has developed in it a product which will precipitate any other specimen of human blood, and, under the proper conditions, will not precipitate the blood of any other animal.

The test is carried out as follows: With proper surgical care there is injected into the peritoneal cavity of a rabbit every two or three days for five or six times, about 8 to 10 cubic centimeters of human blood serum, which may most conveniently be obtained by expressing blood from a recently delivered placenta, and keeping it aseptic. A week after the last injection into the rabbit the carotid arteries are cut and the blood collected, put on the ice and kept. The humanized rabbit serum separates clear as the clot contracts. This is collected and added to the solution of the stain to be examined. The stain should be placed in distilled water or physiological salt solution and shaken till the color of the solution is very faintly discernible. (In concentrated solutions the precipitate will be formed with blood serum of other animals, but the more dilute the solution and the more prompt the precipitate the greater the probability that the blood is human.) Or, if the stain dissolves easily it should be diluted

Vibert, Nouv. Dict. de Méd. et de Chir. Pract. p. 408, and Arch. de Physiol., 1882.

29 Mason, Ann. d'Hyg., 1885, 542. 30 Ewell, Medico-Legal Journ., New York, Sept., 1892.

1 Chapman, Med. Jurispur., 3d ed., 1903, p. 88.

3 Uhlenhut, Deut. Med. Wochenschr., Feb. 7th, 1901.

till the color is very faint. Strube33 obtained marked reactions when the blood to be examined was diluted to one part in a thousand of salt solution. With no blood other than the homologous did he get a positive test in a dilution greater than one part in one hundred. To 2 or 3 cubic centimeters of the diluted blood-stain solution, in a testtube, are added about ten drops of the humanized rabbit serum. If the blood stain is one of human blood, there appears a precipitate in the solution in about ten minutes which is complete and flocculent in about half an hour. If the stain is from the blood of some other animal there may appear a precipitate after several hours, but there will be no prompt appearance of the precipitate, as with human blood.

The test has been tried under many varying conditions and found very satisfactory. Layton considers34 that in dilutions of one part in five hundred the differentiation from all species of animals, even monkeys, can be made. Nuttall35 tested forty-six specimens of blood from apes and found that certain species gave a precipitate equal to that of man, but that other species, while they gave precipitates, did not give as great a quantity. Of some five hundred kinds examined no other animal's blood except monkeys gave the same reaction. The age of the blood stain has no influence on the test, nor, except in a very few instances, 36 does the material on which the blood is depos

ited.

The test has been accepted by several of the European governments,37 as in the case of the Kishineff massacres in Russia. In the United States, in the case of the State of Delaware v. Elmer Collins, acquitted of the murder of his wife by the court of general sessions, Delaware, on March 25, 1903, the test was accepted as better than any other, but not free from reasonable doubt.38 In the case of the Commonwealth of Pennsylvania v. Bechtel, for the murder of her

Strube, Deutsch. med. Wochenschr., Phila. Med. Journ., March 12th, 1904, June 2, 1902. by Dr. Robin, the physician who made the blood examination:

1903.

Layton, Amer. Medicine, June 6,

Nuttall, Journal of Hygiene, Vol. I., No. 1, 1901; Brit. Med. Jour., Sept. 14, 1901, and April 5, 1902.

On the morning of April 12, 1902, a woman, the wife of a young farmer, Elmer Collins, residing near Laurel, Del., was found murdered in the barn. A most valuable paper on this She was lying on her right side, with question, from the forensic point of the face somewhat buried in the ground, view, by Graham-Smith and Sanger, is to be found in the Journ. of Hygiene, Vol. III., No. 2, 1903.

"Russky Vratch, II., 37; an article by P. N. Diatroptoff.

The following report of the case is given in the New York Med. Journ. and VOL. III. MED. JUR.-17.

and with one foot projecting over the doorsill. Her skull was fractured in the occipital and parietal regions, and the throat cut below the cricoid cartilage, two attempts at cutting having been made, and the wound concealed by a fascinator which was tied around the

daughter, the test was accepted as authoritative in spite of the arguments of the defense that the test is still in its infancy and not yet

neck. The husband was accused of the crime, and appeared as the defendant in the case.

The trial, which was the most extensive ever held in the old court house at Georgetown, presented many dramatic situations, psychological studies, and points of medico-legal interest; but, as the defendant was acquitted on the ground of a "reasonable doubt," a discussion of the more interesting medico-legal points brought out in this case would not be justifiable, now that he is legally an innocent man.

termined by the guaiacum and hemin tests. As these are well known, there would be no need of describing either of them, were it not that a slight but useful modification in the technique of the guaiacum test was introduced by the writer. The test as modified is as follows:

The alcoholic solution of guaiacum is freshly prepared by dropping a few pieces of the gum into a beaker containing some 95 per cent alcohol. In about five or ten minutes the alcohol will have dissolved enough of the gum The theory of the state was that the for the purpose. A good-sized piece of woman was murdered in the corncrib white filter paper is then moistened and then dragged to the adjoining barn. with the solution. A drop or two of Evidence in support of this theory con- distilled water is placed over the sussisted in the blood-stained floor and pected stain, and gently rubbed by part of the partition in the corncrib, means of a platinum needle. A loopthe presence of raveling from her dress ful of the solution of the stain is then beneath a projecting nail on the door- placed on the guaiac filter paper, and sill of the barn, the ends of the threads turpentine that has been aërated for pointing inward and the position of the thirty minutes poured over the resultwoman with her instep resting over the ing spot. In the presence of the slightdoorsill. The defense was forced to ad- est trace of blood, the spot formed by mit this theory to be correct, only as the suspected solution will gradually serting that somebody other than the turn blue. By the use of the filter husband committed the deed. In view paper, the reaction is rendered distinct of this admission, and in view of the and unmistakable, and, as has been fact that the presence of blood in the shown in this case, can be demonstrated corncrib was not accounted for by the to a jury much more satisfactorily than defendant, who stated that he had not by the ordinary methods. A number of seen that blood there before, we are other substances which oxidize guajustified in assuming that the theory of iacum were tried with this method, but the state, at least as to the place where in no instance could the reaction be the murder was committed, was sub- mistaken for the characteristic spot stantially correct. This theory was resulting from blood. In the case of founded on the presence in the corncrib iron and other oxidizers the blue spot of supposed human blood, the identifi- appears at once and gradually fades, cation of which was made by the writer. whilst in the case of blood the spot Several pieces of board, chicken ma- turns blue slowly and persists. Morenure, and chips of wood spotted with over, other oxidizers turn the guaiacam what looked like blood, were submitted blue before the addition of turpentine. to me for examination. No indications I am convinced by the results of exwere furnished as to the place or places periments that the guaiacum test, perfrom which these objects were obtained. formed as outlined above, is as delicate Only after the examination was com- and certain as any test for blood. plete and the results communicated to 2. Microscopical examination. the attorney general, did the writer examination was made in the usual learn that some of the pieces were taken manner. The most satisfactory menfrom the flooring and partition of the struum was found to be Ranvier's cornerib, others from the chicken iodized serum (potassium iodid, 2 house, the chicken manure from the parts; saturated watery solution of garden, and again others from the iodin, 100 parts). The reason for this preference is that the iodin stains starch and vegetable cells as well as spores of molds which may closely re

stable.

The following tests were made: 1. The nature of the stains was

de

This