[1] Landell received patents in Brazil and the United States during the first decade of the 1900s in which he also included designs that he claimed could transmit voice using radio waves.

A biographical review recounted that he "...invented his apparatus in Porto Alegre, and as soon as he arrived in São Paulo in 1896, he began with preliminary experiments, to achieve his object — to transmit human voice through the air.

In addition, he offered to establish two facilities in England, dedicated to providing care for the sons and daughters of soldiers recently killed in the Second Boer War.

In late 1900, a Rio de Janeiro newspaper carried an article about an English invention, Colonel George Edward Gouraud's "Gouraudphone" (rendered as Gouraudphono in Portuguese), which was a high-powered megaphone designed for long-distance communication.

"[6] Dr. José Rodrigues Botet took exception to this report, and the December 16, 1900 issue of the La Voz de España carried a letter from him insisting that it was actually Landell who deserved credit for developing the underlying technology used by the Gouraudphone.

Botet's letter stated that over the years he had personally witnessed Landell, working alone, develop advanced wire and wireless telegraphy and telephony equipment, while never receiving the recognition he deserved as "Brazil's eminent son".

Two configurations were described: a full design, known as the "Tellogostomo", and a simpler version, called the "Telauxiophone": The names specified for transmissions made through water were Telhydrauliograph for telegraphic signalling, and Telhydrauliophone for telephonic usage.

[15] Ferrareto stated: the existing evidence points, therefore, to the success of Landell de Moura in the transmission and reception of voice even though the quality did not allow the immediate practical application of the devices created by the Brazilian.

Consciousness that did not exist in Brazil then.The qualification and stabilization of the signal would depend on technological advances that would be made a little later, mainly through John Ambrose Fleming, Reginald Fessenden, Edwin Howard Armstrong and Lee De Forest.

[19] On January 21, 2011, Brazil issued a stamp commemorating the 150th anniversary of Landell's birth, which shows him using a device described in one of his 1904 United States patents.