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Primary Sources: Identifying Evidence: False Teeth

Dr. Nathan C. Keep provided dental testimony during the trial of John Webster. It was the first trial in which dental evidence was introduced, and one of the first to use forensics at all. Along with reading Dr. Keep's testimony below, you can take a look at Parkman's dental cast and other 19th century medical items in this site's Gallery.

I am a surgeon-dentist; have been in the practice of my profession, thirty years, in this city; now live, adjoining the residence of Dr. Winslow Lewis, Jr. I have given attention, both to artificial and natural teeth.

I knew the late Dr. George Parkman. I became acquainted with him, as early as 1825, when I was a student of medicine with Dr. John Randall. Dr. Parkman was sick at the time, and was attended by Dr. Randall, and I afterwards called at his house, myself. Our acquaintance began from that period; and since 1825, he had employed me as his family dentist, and called on me, himself, whenever he needed any assistance or advice in the care of his teeth.

Some mineral teeth were shown to me, by Dr. Lewis, on Monday, December 3d, on my return to Boston from Springfield. I recognized them, as the teeth which I had made for Dr. Parkman, in 1846. [The blocks of teeth taken from the furnace, were here exhibited to the witness.] These blocks, now shown to me, are the same which I then recognized as having made for Dr. Parkman.

Dr. Parkman's mouth was a very peculiar one: so marked, in respect to its shape, and the relation of the upper and lower jaws, that the impression of it on my mind was very distinct. I remember the peculiarities of the lower jaw, with great exactness. The circumstances connected with the ordering of these artificial teeth by Dr. Parkman, were somewhat peculiar.

[Mr. Sohier objected to the witness's detailing these circumstances. But the Court thought the statement of them admissible, so far as they went to explain the witness's means of identification.]

When Dr. Parkman ordered the teeth, he inquired how long it would take to prepare them; and, upon my asking his reason for the inquiry, he replied, that the Medical College, (which was then building,) was going to be opened with some inaugural ceremonies, on a given day; and as he was expected to be there, and should perhaps have to make a speech, he wished to have the set finished by that time, or he did not wish to have them at all. The interval named, was rather a short one; but I undertook to fulfil the order. The peculiarities of the mouth made it a very difficult case, requiring the exercise of as much skill and care as could be bestowed upon it. I began the undertaking as soon as possible; gave a large part of my time to it; saw the work frequently, while in progress, under the care of my assistant; and, from the circumstances attending the expedition necessarily used, I remember, very distinctly, the particulars of completing the set; more, than in ordinary cases.

I began, in the usual way, with taking an impression of the Doctor's mouth; -- an exact fac-smile of his two jaws. This was done by applying soft wax (beeswax) in a piece of metal, to lower the jaw, and then pressing it down, till the wax became cold. After the impression was thus taken, it was oiled, and liquor plaster poured in, which was hardened in about ten minutes, and produced an exact copy of the jaw; -- of the surface of the jaw, where the teeth were wanting, and of the teeth themselves, or any stump, where such teeth, or stump, still remained. A like process gave an exact fac-smile, or impression of the upper-jaw. [The witness here produced plaster-casts of an upper and lower jaw.] This, is the plaster-cast, [exhibiting it to the Court and jury,] of Dr. Parkman's lower jaw, taken from life. It had in it, as the cast shows, four natural teeth, and three roots, or stumps.

The next step was, to obtain the metallic plate, fitting over the gum, and between the teeth, upon which to insert the artificial teeth. This was done, by first getting up a trial-plate. The trial-plate is usually made of copper, or some soft metal, and is procured by making, what is called, a male and female metallic punch and die, from castings taken from the plaster-cast. These castings are, one, of zinc or brass, and the other, of a softer metal, -- tin, or, tin and lead. The copper, from which the trial-plate is to be made, is put between these castings, and, sufficient pressure being exerted upon them, an impression is produced, exactly corresponding to the shape of the punch, and that of the plaster cast. This trial-plate is then put into the mouth; and if found to correspond exactly with the shape of the jaw, the interstices between the teeth, &c., it shows that the castings are proper to produce the gold plate, ultimately to be used as the basis of the set, or block.

Here, is the trial-plate, accompanying the plaster-cast, which was fitted into Dr. Parkman's mouth, and found to correspond exactly with the shape of his lower jaw, teeth, &c. [Here, the witness produced a thin, indented strip of copper, exactly fitting to the shape of the lower jaw, as represented in the plaster-cast, with interstices for the admission of the natural teeth.]

Dr. Parkman, had no natural teeth remaining in his upper jaw. Here, is the trial-plate, [producing it,] exhibiting the form of his upper jaw, and to which the gold plate, used for setting the teeth, exactly corresponded. Of course, it needed no perforations for the admission of the teeth, when applied to the natural jaw.

After the trial-plates were obtained, the gold plates were then made, and fitted into the Doctor's mouth.

The impressions, or fac-smiles, of the two jaws, separately, being thus obtained, the next step, was to get their relative position, when in connection; or something, which should show, how they fitted together.

For this purpose, wax was again applied to both his upper and lower jaw, and he then closed his mouth, so as to leave an impression of his two jaws upon different sides of the same piece of wax. Plaster was then run into the two impressions, and pains taken, before the moulds separated, to mark their relative position, by means of an articulation, as shown in the moulds exhibited. [The witness here produced a second mould, or cast, of Dr. Parkman's mouth, showing a representation of his upper and lower jaw, as when the two were shut together. It consisted, like the other, of two pieces, representing the upper and lower jaw, but which fitted together by means of articulation, or coupling, spoken of, in one absolute position.]

The relative connection of Dr. Parkman's jaws, (as shown in this model,) was a peculiar one. The receding of the upper jaw, and the projection of the lower one, were strongly marked; showing an unusual length of chin: differing, however, in conformation, from that of others, who have merely a prominent chin.

The next step, afer obtaining a fac-similie of the jaws in the way spoken of, was to fit on the teeth to the plate, of the right length. The teeth, themselves, and what was to constitute an artificial gum, were made of the proper material, in a soft mass, like clay, and put into moulds, to bake or harden. Before baking, we have to make an enlargement, to allow for shrinking. The shape of Dr. Parkman's lower jaw, rendered this difficult. The teeth were then baked in a muffle, not exposed directly to the fire.

The teeth, in the case of the upper jaw, where there were no natural teeth remaining, were, at first, made all in one set; which, before baking, was cut into three blocks, by seperations bhind the eye-teeth. The lower teeth, also, consisted of three blocks, that were not made whole, at first, in concsequence of the natural teeth. Of these lower blocks, the largest, or longest, was that, on the left side; the next largest, that, on the right side; and a smaller block, of two or three teeth, in front, completed the set.

All these three blocks fitted to one plate, and went into the mouth, together. The three upper blocks, were, also, all on one plate. The two sets were connected togehter by spiral springs, which enabled the wearer to open and shut his mouth, with less danger of their being displaced. The teeth were fastened in, with platinum pins. I have another model, shoing the length of the lower teeth. [Produces it, and exhibits it to the Court and jury.]

In baking the front block of the lower jaw, an accident happened to one of the teeth, which rendered it necessary to make a new block. This was so shortly before the time fixed for the completeion of the set, that it was necesary to work all night, to repair the accident; and when we got them done, the next day -- I mean Dr. Noble, my assistant, and myself -- it only wanted thirty minutes, to the time fixed for the commencement of the ceremonies at the College.

[The Court here took a recess, in consequence of an alarm of fire at the lodgings of the Attorney General, who requested leave of abscence, to preserve valuable papers. Mr. Clifford having returned in a few minutes, the trial proceeded.]

Dr. Keep, resumes -- I did not feel certain that all was completed, as I should finally desire it to be, and requested the Doctor to call again, and show me his teeth. When he next called, he remarked, that he did not feel as if he had room enough for his tongue. In order to obviate that difficulty, I ground the inside fo the lower blocks, next to the tongue, so as to make rmore room. This grinding was somewhat difficult, in consequence of the teeth being in the plate, and becuse it had to be done with a very small wheel. The grinding removed the pink color from the gum, and also the enamel from the teeth on the inside, and somewhat defaced their beauty. The shape of the space ground out, was peculiar, from the size of the wheel, which was not larger than a cent.

I saw Dr. Parkman afterwards, occasionally, for the purpose of making such slight alterations, or repairs, upon his teeth, as were needed. The last time that I saw him, to do anything to his teeth, was about two weeks previous to his disappearance. Having broken a spring, he called upon me, late one evening, to repair it. It was as late as ten o'clock, or after; and being unwell, I had retired for the night. The person who went to the door, happening to know Dr. Parkman, asked him in, and came up and told me that it was him. Out of regard for him, I sent word that I would come down and attend to him, and dressed, as soon as possible. The Doctor told me his trouble; and I took out his teeth, both upper and lower set, examined them all over, to see that every part was right, repaired the spring, and spent half an hour doing what was necessary. This was my last professional intercourse with him. He called on me, however, the day before his disappearance, and stayed some fifteen minutes, inquiring about a servant that had lived with me.

I left the city, the Wednesday following, (November 28th,) and went into the country, to Longmeadow, to spend Thanksgiving, and returned the Monday after. I had heard of the Doctor's disappearance before I left. On my return, Dr. Winslow Lewis Jr., presented to me these three portions of mineral-teeth, [referring again to the blocks taken from the furnace,] saying, that he was requested to bring them to me for examination. On looking at them, I recognized them to be the same teeth that I had made for Dr. Parkman. The most perfect portion that remained, was that block, that belonged to the left lower jaw. [holding it in his hand.] I recognized the shape and the outline, as being identical with the impression left on my mind, of those that I had labored on so long. [Here, the witness was strongly agitated.] Several of the other portions had been very much injured by fire. I proceeded to look for the models, by which these teeth were made. On comparing the most perfect block with the model, the resemblance was so striking, that I could no longer have any doubt that they were his. [Here, the witness was so overcome by his feelings, as to be unable, for a moment, to proceed. The prisoner exhibited no signs of emotion.]

There was sufficient left of these blocks, to show where they belonged. This, in my right hand, [holding it up,] belongs to the right upper jaw. This, to the left upper jaw; and this, to the front portion of the upper jaw. The three parts make up the whole of the upper set. The left lower block is nearly entire. The block attached to it, I take to be the right lower block, from exculsion. This last, certainly does not belong elsewhere ; and, as long as we have found places for the others, I infer that this must belong in the place not supplied. There is a piece not identified, which may, or may not be, the small front block, (of two or three teeth,) of the lower jaw. I identify and assign places for five pieces, and there is one other piece not identified. These would, together, make the six pieces of the set. I find the platinum pins remain attached to the teeth.

[The witness here exhibited to the jury, and afterwards to the Court, the blocks of teeth in connection with the plaster-model or cast : calling attention, particularly, to the coincidence between the left lower block, and the model. He also pointed out the place of the grinding, showing a roughening of the inside, with a slight concave perpendicular indentation.]

I found more or less imbedded with these teeth, portions of gold, and also minute portions of the natural bone of the jaw ; -- what is called cancellated bone, from its peculiar- shaped cells.

To a juror. -- I saw the set of teeth in the Doctor's mouth, at the last interview.

Direct, again. -- The presumption is very strong, that they went into the fire in the head, or with some portion of it, or in some way muffled. These mineral-teeth, when worn, inbibe moisture ; and, if suddenly thrown into the fire, or heated with great rapidity, the outside becomes glazed, and the expansive power of the steam which is generated inside, explodes them. If put into the fire, surrounded by flesh, or other muffling substance, on the contrary, the temperature would be raised more gradually, and the moisture would evaporate from them, slowly. I have known such explosions to take place with new teeth, when heated suddenly. In fact, it is always necessary to take great care to heat them gradually ; and, with a set which had been worn, I should expect nothign else, if heated suddenly, then that they would fly into innumerable pieces. Another circumstance seems to indicate that they went into the fire, in the head, or together ; and that is, that the spiral springs would have thrown them apart, if not confined in some way, when thrown into the furnace. When the teeth were brought to me, the two blocks were in one mass as now shown to me.

Dr. Lester Noble, now of Baltimore, was the assistant, whom I have mentioned.

Cross-examined by Mr. Sohier. -- All these teeth came to me, at the same time, from Dr. Lewis, on the Monday after Dr. Webster's arrest. I have used no effort to bring to recollection, these facts, connected with the manufacture of this set of teeth for Dr. Parkman. In reply to your question, "When they first came to mind mind after his disapearance?" I can hardly say, when they were ever out of my mind. They always occured to me, whenever I met the Doctor. They were in my mind, when Dr. Lewis first showed the teeth to me; and I immediately said, "Dr. Parkman is gone: we shall see him no more." [The witness, and many of the audience, were here affected to tears.]

I recognized them at once, without the moulds, and then went to look for the moulds. This name [of Dr. Parkman, on the mould ; shown to the jury, ] was written upon it, at the time it was made. They were kept in my cellar, where I had put them away. I keep my moulds, mainly, to provide against any accident which may happen to the set of teeth, made from them. I had before fitted parts of a set of teeth for Dr. Parkman ; -- a block for this left lower jaw, where the absorption is shown. This absorption occured while he wore that block. This was before he went to Europe. I took a cast of his jaw, at that time.

I first heard of Dr. Parkman's disappearance, Saturday night, November 24th, before going into the country. I read the advertisement in the newspaper.

Direct, again. -- Dr. Parkman wore no single mineral-teeth. The natural teeth, which he had remaining, were one tooth, and two roots, on the left side, and three teeth and one root upon the right side, in the following order : -- beginning from behind, on the left side, two roots, then a tooth, (the eye-tooth,) then a vacancy ; then, upon the other side, three teeth in succession, then a root, or stump. The teeth remaining, upon the right side, are one front tooth, the eye-tooth, the first bi-cuspid, and the root of the second bi-cuspid. Two roots of natural teeth were exhibited to me, said to be found among the ashes. One of them, at the time of the examination before the grand jury, was still adhering to the largest block. [Witness identified it, now seperate from the block.] There was a third block, adhering to the two now connected together, united with them, by means of slag, or some other matter, when the teeth were first shown to me. It has since been broken apart. [It was stated by Mr. Clifford, and acceded to by Mr. Sohier, that this seperation had taken place, when Mr. Sohier, in company with the counsel for the Government, was examining the teeth at the City Marshal's office, previous to the trial.]

Take a look at Parkman's dental cast and other 19th century medical items in this site's Gallery.

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