Are Eligible for Patents? Part I

.......To what kinds of thing should the patent system apply is a question that has troubled the US courts since the middle of the 19th century. The grandiose dreams or delusions of Samuel Morse brought the question to the Supreme Court in 1850, when the validity of his patent on the telegraph was challenged. The Court upheld most, but not all, of Morse’s patent. Morse’s achievement, as the Supreme Court perceived it, was overcoming the problem that, when a simple circuit transmitted a signal, that signal sank into the noise on the line after going 20 or 30 miles. Many others had failed to solve the problem. ‘‘The great difficulty in their way,’’ the Supreme Court said, ‘‘was the fact that the galvanic current, however strong in the beginning, became gradually weaker as it advanced on the wire; and was not strong enough to produce a mechanical effect, after a certain distance had been traversed.’’ (See Figures 1 and 2.) To send a signal from Baltimore to Washington would require thousands of volts and high currents— not feasible at a time when making a pickled frog’s legs twitch was a major scientific achievement in the application of ‘‘electro-galvanic force.’’ Morse’s great invention, the Supreme Court said, was his ‘‘plan for combining two or more electric or galvanic circuits, with independent batteries for the purpose of overcoming the diminished force of electromagnetism in long circuits.’’ This is illustrated in Figure 3. Thus, his invention replaced the simple circuit of Figure 1 with a cascade of relays (called ‘‘repeaters’’), which he spaced about every 15 or 20 miles. The intervals were sufficiently short that the signal was restored regularly to substantially its initial level before the noise could swamp it out. In other words, Morse cascaded a series of nonlinear amplifiers, each of which supplied power to the following amplifier in the series, so that each time the signal was rescued from the noise before signal amplitude fell to the noise level. The resulting graph of the signal would then be as if Figure 2 were replicated side by side many times toward the right, with a vertical displacement upward sufficient to keep the total amplitude from ever falling down to the noise amplitude level. See Figure 4. Morse’s patent claimed the invention in a number of different legally acceptable ways. The Supreme Court saw no problem with Morse’s claim to his particular apparatus or to his claiming a process for telecommunications by means of using his apparatus. But Morse had imperial dreams: In his famous (or notorious) claim 8, he also claimed the use of the electromagnetic force (EMF) or galvanic current, however developed, for transmitting intelligible information at any distance. The Supreme Court held this broadest of his claims invalid. The Court pointed to the fact that Morse had not described every possible way to use EMF for telecommunications, so as to enable others to engage in such uses. Yet, he would shut the door against patents for others who in fact discovered and Figure 1. The telegraph problem: transmitting signals over long distance. continued on p. 92 Micro Law